diff --git a/native/chat/chat-input-bar.react.js b/native/chat/chat-input-bar.react.js
index af825bf20..ee942b29e 100644
--- a/native/chat/chat-input-bar.react.js
+++ b/native/chat/chat-input-bar.react.js
@@ -1,1414 +1,1419 @@
 // @flow
 
 import Icon from '@expo/vector-icons/Ionicons.js';
 import invariant from 'invariant';
 import _throttle from 'lodash/throttle.js';
 import * as React from 'react';
 import {
   View,
   TextInput,
   TouchableOpacity,
   Platform,
   Text,
   ActivityIndicator,
   TouchableWithoutFeedback,
   NativeAppEventEmitter,
 } from 'react-native';
 import { TextInputKeyboardMangerIOS } from 'react-native-keyboard-input';
 import Animated, {
   EasingNode,
   FadeInDown,
   FadeOutDown,
 } from 'react-native-reanimated';
 import { useDispatch } from 'react-redux';
 
 import {
   moveDraftActionType,
   updateDraftActionType,
 } from 'lib/actions/draft-actions.js';
 import {
   joinThreadActionTypes,
   joinThread,
   newThreadActionTypes,
 } from 'lib/actions/thread-actions.js';
 import { createLoadingStatusSelector } from 'lib/selectors/loading-selectors.js';
 import { threadInfoSelector } from 'lib/selectors/thread-selectors.js';
 import { userStoreSearchIndex } from 'lib/selectors/user-selectors.js';
 import { colorIsDark } from 'lib/shared/color-utils.js';
 import { useEditMessage } from 'lib/shared/edit-messages-utils.js';
 import {
   getTypeaheadUserSuggestions,
   getTypeaheadRegexMatches,
   type Selection,
   getMentionsCandidates,
 } from 'lib/shared/mention-utils.js';
 import {
   useNextLocalID,
   trimMessage,
   useMessagePreview,
   messageKey,
   type MessagePreviewResult,
 } from 'lib/shared/message-utils.js';
 import SearchIndex from 'lib/shared/search-index.js';
 import {
   threadHasPermission,
   viewerIsMember,
   threadFrozenDueToViewerBlock,
   threadActualMembers,
   checkIfDefaultMembersAreVoiced,
   draftKeyFromThreadID,
+  useThreadChatMentionCandidates,
 } from 'lib/shared/thread-utils.js';
 import type { CalendarQuery } from 'lib/types/entry-types.js';
 import type { LoadingStatus } from 'lib/types/loading-types.js';
 import type { PhotoPaste } from 'lib/types/media-types.js';
 import { messageTypes } from 'lib/types/message-types-enum.js';
 import type {
   SendEditMessageResponse,
   MessageInfo,
 } from 'lib/types/message-types.js';
 import type { Dispatch } from 'lib/types/redux-types.js';
 import { threadPermissions } from 'lib/types/thread-permission-types.js';
 import {
   type ThreadInfo,
   type ClientThreadJoinRequest,
   type ThreadJoinPayload,
   type RelativeMemberInfo,
 } from 'lib/types/thread-types.js';
 import { type UserInfos } from 'lib/types/user-types.js';
 import {
   type DispatchActionPromise,
   useServerCall,
   useDispatchActionPromise,
 } from 'lib/utils/action-utils.js';
 
 import { ChatContext } from './chat-context.js';
 import type { ChatNavigationProp } from './chat.react.js';
 import {
   MessageEditingContext,
   type MessageEditingContextType,
 } from './message-editing-context.react.js';
 import type { RemoveEditMode } from './message-list-types.js';
 import TypeaheadTooltip from './typeahead-tooltip.react.js';
 import Button from '../components/button.react.js';
 // eslint-disable-next-line import/extensions
 import ClearableTextInput from '../components/clearable-text-input.react';
 import type { SyncedSelectionData } from '../components/selectable-text-input.js';
 // eslint-disable-next-line import/extensions
 import SelectableTextInput from '../components/selectable-text-input.react';
 import SingleLine from '../components/single-line.react.js';
 import SWMansionIcon from '../components/swmansion-icon.react.js';
 import {
   type InputState,
   InputStateContext,
   type EditInputBarMessageParameters,
 } from '../input/input-state.js';
 import KeyboardInputHost from '../keyboard/keyboard-input-host.react.js';
 import {
   type KeyboardState,
   KeyboardContext,
 } from '../keyboard/keyboard-state.js';
 import { getKeyboardHeight } from '../keyboard/keyboard.js';
 import { getDefaultTextMessageRules } from '../markdown/rules.react.js';
 import {
   nonThreadCalendarQuery,
   activeThreadSelector,
 } from '../navigation/nav-selectors.js';
 import { NavContext } from '../navigation/navigation-context.js';
 import { OverlayContext } from '../navigation/overlay-context.js';
 import type { OverlayContextType } from '../navigation/overlay-context.js';
 import {
   type NavigationRoute,
   ChatCameraModalRouteName,
   ImagePasteModalRouteName,
 } from '../navigation/route-names.js';
 import { useSelector } from '../redux/redux-utils.js';
 import { type Colors, useStyles, useColors } from '../themes/colors.js';
 import type { LayoutEvent } from '../types/react-native.js';
 import { type AnimatedViewStyle, AnimatedView } from '../types/styles.js';
 import Alert from '../utils/alert.js';
 import { runTiming } from '../utils/animation-utils.js';
 import { exitEditAlert } from '../utils/edit-messages-utils.js';
 import { nativeTypeaheadRegex } from '../utils/typeahead-utils.js';
 
 /* eslint-disable import/no-named-as-default-member */
 const { Value, Clock, block, set, cond, neq, sub, interpolateNode, stopClock } =
   Animated;
 /* eslint-enable import/no-named-as-default-member */
 
 const expandoButtonsAnimationConfig = {
   duration: 150,
   easing: EasingNode.inOut(EasingNode.ease),
 };
 const sendButtonAnimationConfig = {
   duration: 150,
   easing: EasingNode.inOut(EasingNode.ease),
 };
 
 type BaseProps = {
   +threadInfo: ThreadInfo,
 };
 type Props = {
   ...BaseProps,
   +viewerID: ?string,
   +draft: string,
   +joinThreadLoadingStatus: LoadingStatus,
   +threadCreationInProgress: boolean,
   +calendarQuery: () => CalendarQuery,
   +nextLocalID: string,
   +userInfos: UserInfos,
   +colors: Colors,
   +styles: typeof unboundStyles,
   +onInputBarLayout?: (event: LayoutEvent) => mixed,
   +openCamera: () => mixed,
   +isActive: boolean,
   +keyboardState: ?KeyboardState,
   +dispatch: Dispatch,
   +dispatchActionPromise: DispatchActionPromise,
   +joinThread: (request: ClientThreadJoinRequest) => Promise<ThreadJoinPayload>,
   +inputState: ?InputState,
   +userSearchIndex: SearchIndex,
   +mentionsCandidates: $ReadOnlyArray<RelativeMemberInfo>,
   +parentThreadInfo: ?ThreadInfo,
   +editedMessagePreview: ?MessagePreviewResult,
   +editedMessageInfo: ?MessageInfo,
   +editMessage: (
     messageID: string,
     text: string,
   ) => Promise<SendEditMessageResponse>,
   +navigation: ?ChatNavigationProp<'MessageList'>,
   +overlayContext: ?OverlayContextType,
   +messageEditingContext: ?MessageEditingContextType,
 };
 type State = {
   +text: string,
   +textEdited: boolean,
   +buttonsExpanded: boolean,
   +selectionState: SyncedSelectionData,
   +isExitingDuringEditMode: boolean,
 };
 class ChatInputBar extends React.PureComponent<Props, State> {
   textInput: ?React.ElementRef<typeof TextInput>;
   clearableTextInput: ?ClearableTextInput;
   selectableTextInput: ?React.ElementRef<typeof SelectableTextInput>;
 
   expandoButtonsOpen: Value;
   targetExpandoButtonsOpen: Value;
   expandoButtonsStyle: AnimatedViewStyle;
   cameraRollIconStyle: AnimatedViewStyle;
   cameraIconStyle: AnimatedViewStyle;
   expandIconStyle: AnimatedViewStyle;
 
   sendButtonContainerOpen: Value;
   targetSendButtonContainerOpen: Value;
   sendButtonContainerStyle: AnimatedViewStyle;
 
   clearBeforeRemoveListener: () => void;
   clearFocusListener: () => void;
   clearBlurListener: () => void;
 
   constructor(props: Props) {
     super(props);
     this.state = {
       text: props.draft,
       textEdited: false,
       buttonsExpanded: true,
       selectionState: { text: props.draft, selection: { start: 0, end: 0 } },
       isExitingDuringEditMode: false,
     };
 
     this.setUpActionIconAnimations();
     this.setUpSendIconAnimations();
   }
 
   setUpActionIconAnimations() {
     this.expandoButtonsOpen = new Value(1);
     this.targetExpandoButtonsOpen = new Value(1);
     const prevTargetExpandoButtonsOpen = new Value(1);
     const expandoButtonClock = new Clock();
     const expandoButtonsOpen = block([
       cond(neq(this.targetExpandoButtonsOpen, prevTargetExpandoButtonsOpen), [
         stopClock(expandoButtonClock),
         set(prevTargetExpandoButtonsOpen, this.targetExpandoButtonsOpen),
       ]),
       cond(
         neq(this.expandoButtonsOpen, this.targetExpandoButtonsOpen),
         set(
           this.expandoButtonsOpen,
           runTiming(
             expandoButtonClock,
             this.expandoButtonsOpen,
             this.targetExpandoButtonsOpen,
             true,
             expandoButtonsAnimationConfig,
           ),
         ),
       ),
       this.expandoButtonsOpen,
     ]);
 
     this.cameraRollIconStyle = {
       ...unboundStyles.cameraRollIcon,
       opacity: expandoButtonsOpen,
     };
     this.cameraIconStyle = {
       ...unboundStyles.cameraIcon,
       opacity: expandoButtonsOpen,
     };
 
     const expandoButtonsWidth = interpolateNode(expandoButtonsOpen, {
       inputRange: [0, 1],
       outputRange: [26, 66],
     });
     this.expandoButtonsStyle = {
       ...unboundStyles.expandoButtons,
       width: expandoButtonsWidth,
     };
 
     const expandOpacity = sub(1, expandoButtonsOpen);
     this.expandIconStyle = {
       ...unboundStyles.expandIcon,
       opacity: expandOpacity,
     };
   }
 
   setUpSendIconAnimations() {
     const initialSendButtonContainerOpen = trimMessage(this.props.draft)
       ? 1
       : 0;
     this.sendButtonContainerOpen = new Value(initialSendButtonContainerOpen);
     this.targetSendButtonContainerOpen = new Value(
       initialSendButtonContainerOpen,
     );
     const prevTargetSendButtonContainerOpen = new Value(
       initialSendButtonContainerOpen,
     );
     const sendButtonClock = new Clock();
     const sendButtonContainerOpen = block([
       cond(
         neq(
           this.targetSendButtonContainerOpen,
           prevTargetSendButtonContainerOpen,
         ),
         [
           stopClock(sendButtonClock),
           set(
             prevTargetSendButtonContainerOpen,
             this.targetSendButtonContainerOpen,
           ),
         ],
       ),
       cond(
         neq(this.sendButtonContainerOpen, this.targetSendButtonContainerOpen),
         set(
           this.sendButtonContainerOpen,
           runTiming(
             sendButtonClock,
             this.sendButtonContainerOpen,
             this.targetSendButtonContainerOpen,
             true,
             sendButtonAnimationConfig,
           ),
         ),
       ),
       this.sendButtonContainerOpen,
     ]);
 
     const sendButtonContainerWidth = interpolateNode(sendButtonContainerOpen, {
       inputRange: [0, 1],
       outputRange: [4, 38],
     });
     this.sendButtonContainerStyle = { width: sendButtonContainerWidth };
   }
 
   static mediaGalleryOpen(props: Props) {
     const { keyboardState } = props;
     return !!(keyboardState && keyboardState.mediaGalleryOpen);
   }
 
   static systemKeyboardShowing(props: Props) {
     const { keyboardState } = props;
     return !!(keyboardState && keyboardState.systemKeyboardShowing);
   }
 
   get systemKeyboardShowing() {
     return ChatInputBar.systemKeyboardShowing(this.props);
   }
 
   immediatelyShowSendButton() {
     this.sendButtonContainerOpen.setValue(1);
     this.targetSendButtonContainerOpen.setValue(1);
   }
 
   updateSendButton(currentText: string) {
     if (this.shouldShowTextInput) {
       this.targetSendButtonContainerOpen.setValue(currentText === '' ? 0 : 1);
     } else {
       this.setUpSendIconAnimations();
     }
   }
 
   componentDidMount() {
     const { isActive, navigation } = this.props;
     if (isActive) {
       this.addEditInputMessageListener();
     }
     if (!navigation) {
       return;
     }
     this.clearBeforeRemoveListener = navigation.addListener(
       'beforeRemove',
       this.onNavigationBeforeRemove,
     );
     this.clearFocusListener = navigation.addListener(
       'focus',
       this.onNavigationFocus,
     );
     this.clearBlurListener = navigation.addListener(
       'blur',
       this.onNavigationBlur,
     );
   }
 
   componentWillUnmount() {
     if (this.props.isActive) {
       this.removeEditInputMessageListener();
     }
     if (this.clearBeforeRemoveListener) {
       this.clearBeforeRemoveListener();
     }
     if (this.clearFocusListener) {
       this.clearFocusListener();
     }
     if (this.clearBlurListener) {
       this.clearBlurListener();
     }
   }
 
   componentDidUpdate(prevProps: Props, prevState: State) {
     if (
       this.state.textEdited &&
       this.state.text &&
       this.props.threadInfo.id !== prevProps.threadInfo.id
     ) {
       this.props.dispatch({
         type: moveDraftActionType,
         payload: {
           oldKey: draftKeyFromThreadID(prevProps.threadInfo.id),
           newKey: draftKeyFromThreadID(this.props.threadInfo.id),
         },
       });
     } else if (!this.state.textEdited && this.props.draft !== prevProps.draft) {
       this.setState({ text: this.props.draft });
     }
     if (this.props.isActive && !prevProps.isActive) {
       this.addEditInputMessageListener();
     } else if (!this.props.isActive && prevProps.isActive) {
       this.removeEditInputMessageListener();
     }
 
     const currentText = trimMessage(this.state.text);
     const prevText = trimMessage(prevState.text);
 
     if (
       (currentText === '' && prevText !== '') ||
       (currentText !== '' && prevText === '')
     ) {
       this.updateSendButton(currentText);
     }
 
     const systemKeyboardIsShowing = ChatInputBar.systemKeyboardShowing(
       this.props,
     );
     const systemKeyboardWasShowing =
       ChatInputBar.systemKeyboardShowing(prevProps);
     if (systemKeyboardIsShowing && !systemKeyboardWasShowing) {
       this.hideButtons();
     } else if (!systemKeyboardIsShowing && systemKeyboardWasShowing) {
       this.expandButtons();
     }
 
     const imageGalleryIsOpen = ChatInputBar.mediaGalleryOpen(this.props);
     const imageGalleryWasOpen = ChatInputBar.mediaGalleryOpen(prevProps);
     if (!imageGalleryIsOpen && imageGalleryWasOpen) {
       this.hideButtons();
     } else if (imageGalleryIsOpen && !imageGalleryWasOpen) {
       this.expandButtons();
       this.setIOSKeyboardHeight();
     }
 
     if (
       this.props.messageEditingContext?.editState.editedMessage &&
       !prevProps.messageEditingContext?.editState.editedMessage
     ) {
       this.blockNavigation();
     }
   }
 
   addEditInputMessageListener() {
     invariant(
       this.props.inputState,
       'inputState should be set in addEditInputMessageListener',
     );
     this.props.inputState.addEditInputMessageListener(this.focusAndUpdateText);
   }
 
   removeEditInputMessageListener() {
     invariant(
       this.props.inputState,
       'inputState should be set in removeEditInputMessageListener',
     );
     this.props.inputState.removeEditInputMessageListener(
       this.focusAndUpdateText,
     );
   }
 
   setIOSKeyboardHeight() {
     if (Platform.OS !== 'ios') {
       return;
     }
     const { textInput } = this;
     if (!textInput) {
       return;
     }
     const keyboardHeight = getKeyboardHeight();
     if (keyboardHeight === null || keyboardHeight === undefined) {
       return;
     }
     TextInputKeyboardMangerIOS.setKeyboardHeight(textInput, keyboardHeight);
   }
 
   get shouldShowTextInput(): boolean {
     if (threadHasPermission(this.props.threadInfo, threadPermissions.VOICED)) {
       return true;
     }
     // If the thread is created by somebody else while the viewer is attempting
     // to create it, the threadInfo might be modified in-place
     // and won't list the viewer as a member,
     // which will end up hiding the input.
     // In this case, we will assume that our creation action
     // will get translated into a join, and as long
     // as members are voiced, we can show the input.
     if (!this.props.threadCreationInProgress) {
       return false;
     }
     return checkIfDefaultMembersAreVoiced(this.props.threadInfo);
   }
 
   render() {
     const isMember = viewerIsMember(this.props.threadInfo);
     const canJoin = threadHasPermission(
       this.props.threadInfo,
       threadPermissions.JOIN_THREAD,
     );
     let joinButton = null;
     const threadColor = `#${this.props.threadInfo.color}`;
     const isEditMode = this.isEditMode();
     if (!isMember && canJoin && !this.props.threadCreationInProgress) {
       let buttonContent;
       if (this.props.joinThreadLoadingStatus === 'loading') {
         buttonContent = (
           <ActivityIndicator
             size="small"
             color="white"
             style={this.props.styles.joinThreadLoadingIndicator}
           />
         );
       } else {
         const textStyle = colorIsDark(this.props.threadInfo.color)
           ? this.props.styles.joinButtonTextLight
           : this.props.styles.joinButtonTextDark;
         buttonContent = (
           <View style={this.props.styles.joinButtonContent}>
             <SWMansionIcon name="plus" style={textStyle} />
             <Text style={textStyle}>Join Chat</Text>
           </View>
         );
       }
       joinButton = (
         <View style={this.props.styles.joinButtonContainer}>
           <Button
             onPress={this.onPressJoin}
             iosActiveOpacity={0.85}
             style={[
               this.props.styles.joinButton,
               { backgroundColor: threadColor },
             ]}
           >
             {buttonContent}
           </Button>
         </View>
       );
     }
 
     const typeaheadRegexMatches = getTypeaheadRegexMatches(
       this.state.selectionState.text,
       this.state.selectionState.selection,
       nativeTypeaheadRegex,
     );
 
     let typeaheadTooltip = null;
 
     if (typeaheadRegexMatches && !isEditMode) {
       const typeaheadMatchedStrings = {
         textBeforeAtSymbol: typeaheadRegexMatches[1] ?? '',
         usernamePrefix: typeaheadRegexMatches[4] ?? '',
       };
 
       const suggestedUsers = getTypeaheadUserSuggestions(
         this.props.userSearchIndex,
         this.props.mentionsCandidates,
         this.props.viewerID,
         typeaheadMatchedStrings.usernamePrefix,
       );
 
       if (suggestedUsers.length > 0) {
         typeaheadTooltip = (
           <TypeaheadTooltip
             text={this.state.text}
             matchedStrings={typeaheadMatchedStrings}
             suggestedUsers={suggestedUsers}
             focusAndUpdateTextAndSelection={this.focusAndUpdateTextAndSelection}
           />
         );
       }
     }
 
     let content;
     const defaultMembersAreVoiced = checkIfDefaultMembersAreVoiced(
       this.props.threadInfo,
     );
     if (this.shouldShowTextInput) {
       content = this.renderInput();
     } else if (
       threadFrozenDueToViewerBlock(
         this.props.threadInfo,
         this.props.viewerID,
         this.props.userInfos,
       ) &&
       threadActualMembers(this.props.threadInfo.members).length === 2
     ) {
       content = (
         <Text style={this.props.styles.explanation}>
           You can&rsquo;t send messages to a user that you&rsquo;ve blocked.
         </Text>
       );
     } else if (isMember) {
       content = (
         <Text style={this.props.styles.explanation}>
           You don&rsquo;t have permission to send messages.
         </Text>
       );
     } else if (defaultMembersAreVoiced && canJoin) {
       content = null;
     } else {
       content = (
         <Text style={this.props.styles.explanation}>
           You don&rsquo;t have permission to send messages.
         </Text>
       );
     }
 
     const keyboardInputHost =
       Platform.OS === 'android' ? null : (
         <KeyboardInputHost textInputRef={this.textInput} />
       );
 
     let editedMessage;
     if (isEditMode && this.props.editedMessagePreview) {
       const { message } = this.props.editedMessagePreview;
       editedMessage = (
         <AnimatedView
           style={this.props.styles.editView}
           entering={FadeInDown}
           exiting={FadeOutDown}
         >
           <View style={this.props.styles.editViewContent}>
             <TouchableOpacity
               onPress={this.scrollToEditedMessage}
               activeOpacity={0.4}
             >
               <Text
                 style={[{ color: threadColor }, this.props.styles.editingLabel]}
               >
                 Editing message
               </Text>
               <SingleLine style={this.props.styles.editingMessagePreview}>
                 {message.text}
               </SingleLine>
             </TouchableOpacity>
           </View>
           <SWMansionIcon
             style={this.props.styles.exitEditButton}
             name="cross"
             size={22}
             color={threadColor}
             onPress={this.onPressExitEditMode}
           />
         </AnimatedView>
       );
     }
 
     return (
       <AnimatedView
         style={this.props.styles.container}
         onLayout={this.props.onInputBarLayout}
       >
         {typeaheadTooltip}
         {joinButton}
         {editedMessage}
         {content}
         {keyboardInputHost}
       </AnimatedView>
     );
   }
 
   renderInput() {
     const expandoButton = (
       <TouchableOpacity
         onPress={this.expandButtons}
         activeOpacity={0.4}
         style={this.props.styles.expandButton}
       >
         <AnimatedView style={this.expandIconStyle}>
           <SWMansionIcon
             name="chevron-right"
             size={22}
             color={`#${this.props.threadInfo.color}`}
           />
         </AnimatedView>
       </TouchableOpacity>
     );
     const threadColor = `#${this.props.threadInfo.color}`;
     const expandoButtonsViewStyle = [this.props.styles.innerExpandoButtons];
     if (this.isEditMode()) {
       expandoButtonsViewStyle.push({ display: 'none' });
     }
     return (
       <TouchableWithoutFeedback onPress={this.dismissKeyboard}>
         <View style={this.props.styles.inputContainer}>
           <AnimatedView style={this.expandoButtonsStyle}>
             <View style={expandoButtonsViewStyle}>
               {this.state.buttonsExpanded ? expandoButton : null}
               <TouchableOpacity
                 onPress={this.showMediaGallery}
                 activeOpacity={0.4}
               >
                 <AnimatedView style={this.cameraRollIconStyle}>
                   <SWMansionIcon
                     name="image-1"
                     size={28}
                     color={`#${this.props.threadInfo.color}`}
                   />
                 </AnimatedView>
               </TouchableOpacity>
               <TouchableOpacity
                 onPress={this.props.openCamera}
                 activeOpacity={0.4}
                 disabled={!this.state.buttonsExpanded}
               >
                 <AnimatedView style={this.cameraIconStyle}>
                   <SWMansionIcon
                     name="camera"
                     size={28}
                     color={`#${this.props.threadInfo.color}`}
                   />
                 </AnimatedView>
               </TouchableOpacity>
               {this.state.buttonsExpanded ? null : expandoButton}
             </View>
           </AnimatedView>
           <SelectableTextInput
             allowImagePasteForThreadID={this.props.threadInfo.id}
             value={this.state.text}
             onChangeText={this.updateText}
             selection={this.state.selectionState.selection}
             onUpdateSyncedSelectionData={this.updateSelectionState}
             placeholder="Send a message..."
             placeholderTextColor={this.props.colors.listInputButton}
             multiline={true}
             style={this.props.styles.textInput}
             textInputRef={this.textInputRef}
             clearableTextInputRef={this.clearableTextInputRef}
             ref={this.selectableTextInputRef}
             selectionColor={`#${this.props.threadInfo.color}`}
           />
           <AnimatedView style={this.sendButtonContainerStyle}>
             <TouchableOpacity
               onPress={this.onSend}
               activeOpacity={0.4}
               style={this.props.styles.sendButton}
               disabled={trimMessage(this.state.text) === ''}
             >
               <Icon
                 name="md-send"
                 size={25}
                 style={this.props.styles.sendIcon}
                 color={threadColor}
               />
             </TouchableOpacity>
           </AnimatedView>
         </View>
       </TouchableWithoutFeedback>
     );
   }
 
   textInputRef = (textInput: ?React.ElementRef<typeof TextInput>) => {
     this.textInput = textInput;
   };
 
   clearableTextInputRef = (clearableTextInput: ?ClearableTextInput) => {
     this.clearableTextInput = clearableTextInput;
   };
 
   selectableTextInputRef = (
     selectableTextInput: ?React.ElementRef<typeof SelectableTextInput>,
   ) => {
     this.selectableTextInput = selectableTextInput;
   };
 
   updateText = (text: string) => {
     if (this.state.isExitingDuringEditMode) {
       return;
     }
     this.setState({ text, textEdited: true });
     this.props.messageEditingContext?.setEditedMessageChanged(
       this.isMessageEdited(text),
     );
     if (this.isEditMode()) {
       return;
     }
     this.saveDraft(text);
   };
 
   updateSelectionState: (data: SyncedSelectionData) => void = data => {
     this.setState({ selectionState: data });
   };
 
   saveDraft = _throttle(text => {
     this.props.dispatch({
       type: updateDraftActionType,
       payload: {
         key: draftKeyFromThreadID(this.props.threadInfo.id),
         text,
       },
     });
   }, 400);
 
   focusAndUpdateTextAndSelection = (text: string, selection: Selection) => {
     this.selectableTextInput?.prepareForSelectionMutation(text, selection);
     this.setState({
       text,
       textEdited: true,
       selectionState: { text, selection },
     });
     this.saveDraft(text);
 
     this.focusAndUpdateButtonsVisibility();
   };
 
   focusAndUpdateText = (params: EditInputBarMessageParameters) => {
     const { message: text, mode } = params;
     const currentText = this.state.text;
     if (mode === 'replace') {
       this.updateText(text);
     } else if (!currentText.startsWith(text)) {
       const prependedText = text.concat(currentText);
       this.updateText(prependedText);
     }
 
     this.focusAndUpdateButtonsVisibility();
   };
 
   focusAndUpdateButtonsVisibility = () => {
     const { textInput } = this;
     if (!textInput) {
       return;
     }
 
     this.immediatelyShowSendButton();
     this.immediatelyHideButtons();
     textInput.focus();
   };
 
   onSend = async () => {
     if (!trimMessage(this.state.text)) {
       return;
     }
 
     const editedMessage = this.getEditedMessage();
     if (editedMessage && editedMessage.id) {
       this.editMessage(editedMessage.id, this.state.text);
       return;
     }
 
     this.updateSendButton('');
 
     const { clearableTextInput } = this;
     invariant(
       clearableTextInput,
       'clearableTextInput should be sent in onSend',
     );
     let text = await clearableTextInput.getValueAndReset();
     text = trimMessage(text);
     if (!text) {
       return;
     }
 
     const localID = this.props.nextLocalID;
     const creatorID = this.props.viewerID;
     invariant(creatorID, 'should have viewer ID in order to send a message');
     invariant(
       this.props.inputState,
       'inputState should be set in ChatInputBar.onSend',
     );
 
     this.props.inputState.sendTextMessage(
       {
         type: messageTypes.TEXT,
         localID,
         threadID: this.props.threadInfo.id,
         text,
         creatorID,
         time: Date.now(),
       },
       this.props.threadInfo,
       this.props.parentThreadInfo,
     );
   };
 
   isEditMode = () => {
     const editState = this.props.messageEditingContext?.editState;
     const isThisThread =
       editState?.editedMessage?.threadID === this.props.threadInfo.id;
     return editState && editState.editedMessage !== null && isThisThread;
   };
 
   isMessageEdited = newText => {
     let text = newText ?? this.state.text;
     text = trimMessage(text);
     const originalText = this.props.editedMessageInfo?.text;
     return text !== originalText;
   };
 
   unblockNavigation = () => {
     const { navigation } = this.props;
     if (!navigation) {
       return;
     }
     navigation.setParams({ removeEditMode: null });
   };
 
   removeEditMode: RemoveEditMode = action => {
     const { navigation } = this.props;
     if (!navigation || this.state.isExitingDuringEditMode) {
       return 'ignore_action';
     }
     if (!this.isMessageEdited()) {
       this.unblockNavigation();
       return 'reduce_action';
     }
     const unblockAndDispatch = () => {
       this.unblockNavigation();
       navigation.dispatch(action);
     };
     const onContinueEditing = () => {
       this.props.overlayContext?.resetScrollBlockingModalStatus();
     };
     exitEditAlert({
       onDiscard: unblockAndDispatch,
       onContinueEditing,
     });
     return 'ignore_action';
   };
 
   blockNavigation = () => {
     const { navigation } = this.props;
     if (!navigation || !navigation.isFocused()) {
       return;
     }
     navigation.setParams({
       removeEditMode: this.removeEditMode,
     });
   };
 
   editMessage = async (messageID: string, text: string) => {
     if (!this.isMessageEdited()) {
       this.exitEditMode();
       return;
     }
     text = trimMessage(text);
     try {
       await this.props.editMessage(messageID, text);
       this.exitEditMode();
     } catch (error) {
       Alert.alert(
         'Couldn’t edit the message',
         'Please try again later',
         [{ text: 'OK' }],
         {
           cancelable: true,
         },
       );
     }
   };
 
   getEditedMessage = () => {
     const editState = this.props.messageEditingContext?.editState;
     return editState?.editedMessage;
   };
 
   onPressExitEditMode = () => {
     if (!this.isMessageEdited()) {
       this.exitEditMode();
       return;
     }
     exitEditAlert({
       onDiscard: this.exitEditMode,
     });
   };
 
   scrollToEditedMessage = () => {
     const editedMessage = this.getEditedMessage();
     if (!editedMessage) {
       return;
     }
     const editedMessageKey = messageKey(editedMessage);
     this.props.inputState?.scrollToMessage(editedMessageKey);
   };
 
   exitEditMode = () => {
     this.props.messageEditingContext?.setEditedMessage(null, () => {
       this.unblockNavigation();
       this.updateText(this.props.draft);
       this.focusAndUpdateButtonsVisibility();
       this.updateSendButton(this.props.draft);
     });
   };
 
   onNavigationFocus = () => {
     this.setState({ isExitingDuringEditMode: false });
   };
 
   onNavigationBlur = () => {
     if (!this.isEditMode()) {
       return;
     }
     this.setState(
       { text: this.props.draft, isExitingDuringEditMode: true },
       this.exitEditMode,
     );
   };
 
   onNavigationBeforeRemove = e => {
     if (!this.isEditMode()) {
       return;
     }
     const { action } = e.data;
     e.preventDefault();
     const saveExit = () => {
       this.props.messageEditingContext?.setEditedMessage(null, () => {
         this.setState({ isExitingDuringEditMode: true }, () => {
           if (!this.props.navigation) {
             return;
           }
           this.props.navigation.dispatch(action);
         });
       });
     };
     if (!this.isMessageEdited()) {
       saveExit();
       return;
     }
     exitEditAlert({
       onDiscard: saveExit,
     });
   };
 
   onPressJoin = () => {
     this.props.dispatchActionPromise(joinThreadActionTypes, this.joinAction());
   };
 
   async joinAction() {
     const query = this.props.calendarQuery();
     return await this.props.joinThread({
       threadID: this.props.threadInfo.id,
       calendarQuery: {
         startDate: query.startDate,
         endDate: query.endDate,
         filters: [
           ...query.filters,
           { type: 'threads', threadIDs: [this.props.threadInfo.id] },
         ],
       },
     });
   }
 
   expandButtons = () => {
     if (this.state.buttonsExpanded || this.isEditMode()) {
       return;
     }
     this.targetExpandoButtonsOpen.setValue(1);
     this.setState({ buttonsExpanded: true });
   };
 
   hideButtons() {
     if (
       ChatInputBar.mediaGalleryOpen(this.props) ||
       !this.systemKeyboardShowing ||
       !this.state.buttonsExpanded
     ) {
       return;
     }
     this.targetExpandoButtonsOpen.setValue(0);
     this.setState({ buttonsExpanded: false });
   }
 
   immediatelyHideButtons() {
     this.expandoButtonsOpen.setValue(0);
     this.targetExpandoButtonsOpen.setValue(0);
     this.setState({ buttonsExpanded: false });
   }
 
   showMediaGallery = () => {
     const { keyboardState } = this.props;
     invariant(keyboardState, 'keyboardState should be initialized');
     keyboardState.showMediaGallery(this.props.threadInfo);
   };
 
   dismissKeyboard = () => {
     const { keyboardState } = this.props;
     keyboardState && keyboardState.dismissKeyboard();
   };
 }
 
 const unboundStyles = {
   cameraIcon: {
     paddingBottom: Platform.OS === 'android' ? 11 : 8,
     paddingRight: 5,
   },
   cameraRollIcon: {
     paddingBottom: Platform.OS === 'android' ? 11 : 8,
     paddingRight: 5,
   },
   container: {
     backgroundColor: 'listBackground',
     paddingLeft: Platform.OS === 'android' ? 10 : 5,
   },
   expandButton: {
     bottom: 0,
     position: 'absolute',
     right: 0,
   },
   expandIcon: {
     paddingBottom: Platform.OS === 'android' ? 13 : 11,
     paddingRight: 2,
   },
   expandoButtons: {
     alignSelf: 'flex-end',
   },
   explanation: {
     color: 'listBackgroundSecondaryLabel',
     paddingBottom: 4,
     paddingTop: 1,
     textAlign: 'center',
   },
   innerExpandoButtons: {
     alignItems: 'flex-end',
     alignSelf: 'flex-end',
     flexDirection: 'row',
   },
   inputContainer: {
     flexDirection: 'row',
   },
   joinButton: {
     borderRadius: 8,
     flex: 1,
     justifyContent: 'center',
     marginHorizontal: 12,
     marginVertical: 3,
   },
   joinButtonContainer: {
     flexDirection: 'row',
     height: 48,
     marginBottom: 8,
   },
   editView: {
     marginLeft: 20,
     marginRight: 20,
     padding: 10,
     flexDirection: 'row',
     justifyContent: 'space-between',
   },
   editViewContent: {
     flex: 1,
     paddingRight: 6,
   },
   exitEditButton: {
     marginTop: 6,
   },
   editingLabel: {
     paddingBottom: 4,
   },
   editingMessagePreview: {
     color: 'listForegroundLabel',
   },
   joinButtonContent: {
     flexDirection: 'row',
     justifyContent: 'center',
     alignItems: 'center',
   },
   joinButtonTextLight: {
     color: 'white',
     fontSize: 20,
     marginHorizontal: 4,
   },
   joinButtonTextDark: {
     color: 'black',
     fontSize: 20,
     marginHorizontal: 4,
   },
   joinThreadLoadingIndicator: {
     paddingVertical: 2,
   },
   sendButton: {
     position: 'absolute',
     bottom: 4,
     left: 0,
   },
   sendIcon: {
     paddingLeft: 9,
     paddingRight: 8,
     paddingVertical: 6,
   },
   textInput: {
     backgroundColor: 'listInputBackground',
     borderRadius: 8,
     color: 'listForegroundLabel',
     fontSize: 16,
     marginLeft: 4,
     marginRight: 4,
     marginTop: 6,
     marginBottom: 8,
     maxHeight: 110,
     paddingHorizontal: 10,
     paddingVertical: 5,
   },
 };
 
 const joinThreadLoadingStatusSelector = createLoadingStatusSelector(
   joinThreadActionTypes,
 );
 const createThreadLoadingStatusSelector =
   createLoadingStatusSelector(newThreadActionTypes);
 
 type ConnectedChatInputBarBaseProps = {
   ...BaseProps,
   +onInputBarLayout?: (event: LayoutEvent) => mixed,
   +openCamera: () => mixed,
   +navigation?: ChatNavigationProp<'MessageList'>,
 };
 function ConnectedChatInputBarBase(props: ConnectedChatInputBarBaseProps) {
   const navContext = React.useContext(NavContext);
   const keyboardState = React.useContext(KeyboardContext);
   const inputState = React.useContext(InputStateContext);
   const overlayContext = React.useContext(OverlayContext);
 
   const viewerID = useSelector(
     state => state.currentUserInfo && state.currentUserInfo.id,
   );
   const draft = useSelector(
     state =>
       state.draftStore.drafts[draftKeyFromThreadID(props.threadInfo.id)] ?? '',
   );
   const joinThreadLoadingStatus = useSelector(joinThreadLoadingStatusSelector);
   const createThreadLoadingStatus = useSelector(
     createThreadLoadingStatusSelector,
   );
   const threadCreationInProgress = createThreadLoadingStatus === 'loading';
   const calendarQuery = useSelector(state =>
     nonThreadCalendarQuery({
       redux: state,
       navContext,
     }),
   );
   const nextLocalID = useNextLocalID();
   const userInfos = useSelector(state => state.userStore.userInfos);
 
   const styles = useStyles(unboundStyles);
   const colors = useColors();
 
   const isActive = React.useMemo(
     () => props.threadInfo.id === activeThreadSelector(navContext),
     [props.threadInfo.id, navContext],
   );
 
   const dispatch = useDispatch();
   const dispatchActionPromise = useDispatchActionPromise();
   const callJoinThread = useServerCall(joinThread);
 
   const userSearchIndex = useSelector(userStoreSearchIndex);
 
   const { parentThreadID } = props.threadInfo;
   const parentThreadInfo = useSelector(state =>
     parentThreadID ? threadInfoSelector(state)[parentThreadID] : null,
   );
 
   const mentionsCandidates = getMentionsCandidates(
     props.threadInfo,
     parentThreadInfo,
   );
 
+  const chatMentionCandidates = useThreadChatMentionCandidates(
+    props.threadInfo,
+  );
+
   const messageEditingContext = React.useContext(MessageEditingContext);
 
   const editedMessageInfo = messageEditingContext?.editState.editedMessage;
   const editedMessagePreview = useMessagePreview(
     editedMessageInfo,
     props.threadInfo,
-    getDefaultTextMessageRules().simpleMarkdownRules,
+    getDefaultTextMessageRules(chatMentionCandidates).simpleMarkdownRules,
   );
   const editMessage = useEditMessage();
 
   return (
     <ChatInputBar
       {...props}
       viewerID={viewerID}
       draft={draft}
       joinThreadLoadingStatus={joinThreadLoadingStatus}
       threadCreationInProgress={threadCreationInProgress}
       calendarQuery={calendarQuery}
       nextLocalID={nextLocalID}
       userInfos={userInfos}
       colors={colors}
       styles={styles}
       isActive={isActive}
       keyboardState={keyboardState}
       dispatch={dispatch}
       dispatchActionPromise={dispatchActionPromise}
       joinThread={callJoinThread}
       inputState={inputState}
       userSearchIndex={userSearchIndex}
       mentionsCandidates={mentionsCandidates}
       parentThreadInfo={parentThreadInfo}
       editedMessagePreview={editedMessagePreview}
       editedMessageInfo={editedMessageInfo}
       editMessage={editMessage}
       navigation={props.navigation}
       overlayContext={overlayContext}
       messageEditingContext={messageEditingContext}
     />
   );
 }
 
 type DummyChatInputBarProps = {
   ...BaseProps,
   +onHeightMeasured: (height: number) => mixed,
 };
 const noop = () => {};
 function DummyChatInputBar(props: DummyChatInputBarProps): React.Node {
   const { onHeightMeasured, ...restProps } = props;
   const onInputBarLayout = React.useCallback(
     (event: LayoutEvent) => {
       const { height } = event.nativeEvent.layout;
       onHeightMeasured(height);
     },
     [onHeightMeasured],
   );
   return (
     <View pointerEvents="none">
       <ConnectedChatInputBarBase
         {...restProps}
         onInputBarLayout={onInputBarLayout}
         openCamera={noop}
       />
     </View>
   );
 }
 
 type ChatInputBarProps = {
   ...BaseProps,
   +navigation: ChatNavigationProp<'MessageList'>,
   +route: NavigationRoute<'MessageList'>,
 };
 const ConnectedChatInputBar: React.ComponentType<ChatInputBarProps> =
   React.memo<ChatInputBarProps>(function ConnectedChatInputBar(
     props: ChatInputBarProps,
   ) {
     const { navigation, route, ...restProps } = props;
     const keyboardState = React.useContext(KeyboardContext);
 
     const { threadInfo } = props;
     const imagePastedCallback = React.useCallback(
       imagePastedEvent => {
         if (threadInfo.id !== imagePastedEvent.threadID) {
           return;
         }
         const pastedImage: PhotoPaste = {
           step: 'photo_paste',
           dimensions: {
             height: imagePastedEvent.height,
             width: imagePastedEvent.width,
           },
           filename: imagePastedEvent.fileName,
           uri: 'file://' + imagePastedEvent.filePath,
           selectTime: 0,
           sendTime: 0,
           retries: 0,
         };
         navigation.navigate<'ImagePasteModal'>({
           name: ImagePasteModalRouteName,
           params: {
             imagePasteStagingInfo: pastedImage,
             thread: threadInfo,
           },
         });
       },
       [navigation, threadInfo],
     );
 
     React.useEffect(() => {
       const imagePasteListener = NativeAppEventEmitter.addListener(
         'imagePasted',
         imagePastedCallback,
       );
       return () => imagePasteListener.remove();
     }, [imagePastedCallback]);
 
     const chatContext = React.useContext(ChatContext);
     invariant(chatContext, 'should be set');
     const { setChatInputBarHeight, deleteChatInputBarHeight } = chatContext;
     const onInputBarLayout = React.useCallback(
       (event: LayoutEvent) => {
         const { height } = event.nativeEvent.layout;
         setChatInputBarHeight(threadInfo.id, height);
       },
       [threadInfo.id, setChatInputBarHeight],
     );
 
     React.useEffect(() => {
       return () => {
         deleteChatInputBarHeight(threadInfo.id);
       };
     }, [deleteChatInputBarHeight, threadInfo.id]);
 
     const openCamera = React.useCallback(() => {
       keyboardState?.dismissKeyboard();
       navigation.navigate<'ChatCameraModal'>({
         name: ChatCameraModalRouteName,
         params: {
           presentedFrom: route.key,
           thread: threadInfo,
         },
       });
     }, [keyboardState, navigation, route.key, threadInfo]);
 
     return (
       <ConnectedChatInputBarBase
         {...restProps}
         onInputBarLayout={onInputBarLayout}
         openCamera={openCamera}
         navigation={navigation}
       />
     );
   });
 
 export { ConnectedChatInputBar as ChatInputBar, DummyChatInputBar };
diff --git a/native/chat/message-list-types.js b/native/chat/message-list-types.js
index b4acf2b53..8af253c96 100644
--- a/native/chat/message-list-types.js
+++ b/native/chat/message-list-types.js
@@ -1,128 +1,133 @@
 // @flow
 
 import { useNavigation, useNavigationState } from '@react-navigation/native';
 import invariant from 'invariant';
 import * as React from 'react';
 
+import { useThreadChatMentionCandidates } from 'lib/shared/thread-utils.js';
 import type { ThreadInfo } from 'lib/types/thread-types.js';
 import { type UserInfo } from 'lib/types/user-types.js';
 
 import { ChatContext } from './chat-context.js';
 import type { ChatRouterNavigationAction } from './chat-router.js';
 import type { MarkdownRules } from '../markdown/rules.react.js';
 import { useTextMessageRulesFunc } from '../markdown/rules.react.js';
 import {
   MessageListRouteName,
   TextMessageTooltipModalRouteName,
 } from '../navigation/route-names.js';
 
 export type MessageListParams = {
   +threadInfo: ThreadInfo,
   +pendingPersonalThreadUserInfo?: UserInfo,
   +searching?: boolean,
   +removeEditMode?: ?RemoveEditMode,
 };
 
 export type RemoveEditMode = (
   action: ChatRouterNavigationAction,
 ) => 'ignore_action' | 'reduce_action';
 
 export type MessageListContextType = {
   +getTextMessageMarkdownRules: (useDarkStyle: boolean) => MarkdownRules,
 };
 
 const MessageListContext: React.Context<?MessageListContextType> =
   React.createContext<?MessageListContextType>();
 
 function useMessageListContext(threadInfo: ThreadInfo) {
-  const getTextMessageMarkdownRules = useTextMessageRulesFunc(threadInfo);
+  const chatMentionCandidates = useThreadChatMentionCandidates(threadInfo);
+  const getTextMessageMarkdownRules = useTextMessageRulesFunc(
+    threadInfo,
+    chatMentionCandidates,
+  );
   return React.useMemo(
     () => ({
       getTextMessageMarkdownRules,
     }),
     [getTextMessageMarkdownRules],
   );
 }
 
 type Props = {
   +children: React.Node,
   +threadInfo: ThreadInfo,
 };
 function MessageListContextProvider(props: Props): React.Node {
   const context = useMessageListContext(props.threadInfo);
   return (
     <MessageListContext.Provider value={context}>
       {props.children}
     </MessageListContext.Provider>
   );
 }
 
 type NavigateToThreadAction = {
   +name: typeof MessageListRouteName,
   +params: MessageListParams,
   +key: string,
 };
 function createNavigateToThreadAction(
   params: MessageListParams,
 ): NavigateToThreadAction {
   return {
     name: MessageListRouteName,
     params,
     key: `${MessageListRouteName}${params.threadInfo.id}`,
   };
 }
 
 function useNavigateToThread(): (params: MessageListParams) => void {
   const { navigate } = useNavigation();
   return React.useCallback(
     (params: MessageListParams) => {
       navigate<'MessageList'>(createNavigateToThreadAction(params));
     },
     [navigate],
   );
 }
 
 function useTextMessageMarkdownRules(useDarkStyle: boolean): MarkdownRules {
   const messageListContext = React.useContext(MessageListContext);
   invariant(messageListContext, 'DummyTextNode should have MessageListContext');
   return messageListContext.getTextMessageMarkdownRules(useDarkStyle);
 }
 
 function useNavigateToThreadWithFadeAnimation(
   threadInfo: ThreadInfo,
   messageKey: ?string,
 ): () => mixed {
   const chatContext = React.useContext(ChatContext);
   invariant(chatContext, 'ChatContext should be set');
   const {
     setCurrentTransitionSidebarSourceID: setSidebarSourceID,
     setSidebarAnimationType,
   } = chatContext;
   const navigateToThread = useNavigateToThread();
   const navigationStack = useNavigationState(state => state.routes);
   return React.useCallback(() => {
     if (
       navigationStack[navigationStack.length - 1].name ===
       TextMessageTooltipModalRouteName
     ) {
       setSidebarSourceID(messageKey);
       setSidebarAnimationType('fade_source_message');
     }
     navigateToThread({ threadInfo });
   }, [
     messageKey,
     navigateToThread,
     navigationStack,
     setSidebarAnimationType,
     setSidebarSourceID,
     threadInfo,
   ]);
 }
 
 export {
   MessageListContextProvider,
   createNavigateToThreadAction,
   useNavigateToThread,
   useTextMessageMarkdownRules,
   useNavigateToThreadWithFadeAnimation,
 };
diff --git a/native/chat/message-preview.react.js b/native/chat/message-preview.react.js
index 09c363a12..cea5eeed3 100644
--- a/native/chat/message-preview.react.js
+++ b/native/chat/message-preview.react.js
@@ -1,90 +1,93 @@
 // @flow
 
 import invariant from 'invariant';
 import * as React from 'react';
 import { Text } from 'react-native';
 
 import { useMessagePreview } from 'lib/shared/message-utils.js';
+import { useThreadChatMentionCandidates } from 'lib/shared/thread-utils.js';
 import { type MessageInfo } from 'lib/types/message-types.js';
 import { type ThreadInfo } from 'lib/types/thread-types.js';
 
 import SingleLine from '../components/single-line.react.js';
 import { getDefaultTextMessageRules } from '../markdown/rules.react.js';
 import { useStyles } from '../themes/colors.js';
 
 type Props = {
   +messageInfo: MessageInfo,
   +threadInfo: ThreadInfo,
 };
 function MessagePreview(props: Props): React.Node {
   const { messageInfo, threadInfo } = props;
+
+  const chatMentionCandidates = useThreadChatMentionCandidates(threadInfo);
   const messagePreviewResult = useMessagePreview(
     messageInfo,
     threadInfo,
-    getDefaultTextMessageRules().simpleMarkdownRules,
+    getDefaultTextMessageRules(chatMentionCandidates).simpleMarkdownRules,
   );
   invariant(
     messagePreviewResult,
     'useMessagePreview should only return falsey if pass null or undefined',
   );
   const { message, username } = messagePreviewResult;
 
   let messageStyle;
   const styles = useStyles(unboundStyles);
   if (message.style === 'unread') {
     messageStyle = styles.unread;
   } else if (message.style === 'primary') {
     messageStyle = styles.primary;
   } else if (message.style === 'secondary') {
     messageStyle = styles.secondary;
   }
   invariant(
     messageStyle,
     `MessagePreview doesn't support ${message.style} style for message, ` +
       'only unread, primary, and secondary',
   );
 
   if (!username) {
     return (
       <SingleLine style={[styles.lastMessage, messageStyle]}>
         {message.text}
       </SingleLine>
     );
   }
 
   let usernameStyle;
   if (username.style === 'unread') {
     usernameStyle = styles.unread;
   } else if (username.style === 'secondary') {
     usernameStyle = styles.secondary;
   }
   invariant(
     usernameStyle,
     `MessagePreview doesn't support ${username.style} style for username, ` +
       'only unread and secondary',
   );
   return (
     <Text style={[styles.lastMessage, messageStyle]} numberOfLines={1}>
       <Text style={usernameStyle}>{`${username.text}: `}</Text>
       {message.text}
     </Text>
   );
 }
 
 const unboundStyles = {
   lastMessage: {
     flex: 1,
     fontSize: 14,
   },
   primary: {
     color: 'listForegroundTertiaryLabel',
   },
   secondary: {
     color: 'listForegroundTertiaryLabel',
   },
   unread: {
     color: 'listForegroundLabel',
   },
 };
 
 export default MessagePreview;
diff --git a/native/chat/sidebar-input-bar-height-measurer.react.js b/native/chat/sidebar-input-bar-height-measurer.react.js
index fe9b4e82f..67e7df08d 100644
--- a/native/chat/sidebar-input-bar-height-measurer.react.js
+++ b/native/chat/sidebar-input-bar-height-measurer.react.js
@@ -1,49 +1,58 @@
 // @flow
 
 import * as React from 'react';
 import { View, StyleSheet } from 'react-native';
 
 import { useLoggedInUserInfo } from 'lib/hooks/account-hooks.js';
+import { useThreadChatMentionCandidates } from 'lib/shared/thread-utils.js';
 
 import { DummyChatInputBar } from './chat-input-bar.react.js';
 import { useMessageListScreenWidth } from './composed-message-width.js';
 import { getUnresolvedSidebarThreadInfo } from './sidebar-navigation.js';
 import type { ChatMessageInfoItemWithHeight } from '../types/chat-types.js';
 
 type Props = {
   +sourceMessage: ChatMessageInfoItemWithHeight,
   +onInputBarMeasured: (height: number) => mixed,
 };
 
 function SidebarInputBarHeightMeasurer(props: Props): React.Node {
   const { sourceMessage, onInputBarMeasured } = props;
 
   const width = useMessageListScreenWidth();
 
   const loggedInUserInfo = useLoggedInUserInfo();
+  const chatMentionCandidates = useThreadChatMentionCandidates(
+    sourceMessage.threadInfo,
+  );
   const sidebarThreadInfo = React.useMemo(
-    () => getUnresolvedSidebarThreadInfo({ sourceMessage, loggedInUserInfo }),
-    [sourceMessage, loggedInUserInfo],
+    () =>
+      getUnresolvedSidebarThreadInfo({
+        sourceMessage,
+        loggedInUserInfo,
+        chatMentionCandidates,
+      }),
+    [sourceMessage, loggedInUserInfo, chatMentionCandidates],
   );
   if (!sidebarThreadInfo) {
     return null;
   }
 
   return (
     <View style={[styles.dummy, { width }]}>
       <DummyChatInputBar
         threadInfo={sidebarThreadInfo}
         onHeightMeasured={onInputBarMeasured}
       />
     </View>
   );
 }
 
 const styles = StyleSheet.create({
   dummy: {
     opacity: 0,
     position: 'absolute',
   },
 });
 
 export default SidebarInputBarHeightMeasurer;
diff --git a/native/chat/sidebar-navigation.js b/native/chat/sidebar-navigation.js
index 310082a77..f54ac9d45 100644
--- a/native/chat/sidebar-navigation.js
+++ b/native/chat/sidebar-navigation.js
@@ -1,109 +1,129 @@
 // @flow
 
 import invariant from 'invariant';
 import * as React from 'react';
 
 import { ENSCacheContext } from 'lib/components/ens-cache-provider.react.js';
 import { useLoggedInUserInfo } from 'lib/hooks/account-hooks.js';
 import {
   createPendingSidebar,
   createUnresolvedPendingSidebar,
+  useThreadChatMentionCandidates,
 } from 'lib/shared/thread-utils.js';
-import type { ThreadInfo } from 'lib/types/thread-types.js';
+import type {
+  ThreadInfo,
+  ChatMentionCandidates,
+} from 'lib/types/thread-types.js';
 import type { LoggedInUserInfo } from 'lib/types/user-types.js';
 import type { GetENSNames } from 'lib/utils/ens-helpers.js';
 
 import { ChatContext } from './chat-context.js';
 import { useNavigateToThread } from './message-list-types.js';
 import { getDefaultTextMessageRules } from '../markdown/rules.react.js';
 import type { ChatMessageInfoItemWithHeight } from '../types/chat-types.js';
 
 type GetUnresolvedSidebarThreadInfoInput = {
   +sourceMessage: ChatMessageInfoItemWithHeight,
   +loggedInUserInfo: ?LoggedInUserInfo,
+  +chatMentionCandidates: ChatMentionCandidates,
 };
 function getUnresolvedSidebarThreadInfo(
   input: GetUnresolvedSidebarThreadInfoInput,
 ): ?ThreadInfo {
-  const { sourceMessage, loggedInUserInfo } = input;
+  const { sourceMessage, loggedInUserInfo, chatMentionCandidates } = input;
   const threadCreatedFromMessage = sourceMessage.threadCreatedFromMessage;
   if (threadCreatedFromMessage) {
     return threadCreatedFromMessage;
   }
 
   if (!loggedInUserInfo) {
     return null;
   }
 
   const { messageInfo, threadInfo } = sourceMessage;
   return createUnresolvedPendingSidebar({
     sourceMessageInfo: messageInfo,
     parentThreadInfo: threadInfo,
     loggedInUserInfo,
-    markdownRules: getDefaultTextMessageRules().simpleMarkdownRules,
+    markdownRules: getDefaultTextMessageRules(chatMentionCandidates)
+      .simpleMarkdownRules,
   });
 }
 
 type GetSidebarThreadInfoInput = {
   ...GetUnresolvedSidebarThreadInfoInput,
   +getENSNames: ?GetENSNames,
 };
 async function getSidebarThreadInfo(
   input: GetSidebarThreadInfoInput,
 ): Promise<?ThreadInfo> {
-  const { sourceMessage, loggedInUserInfo, getENSNames } = input;
+  const {
+    sourceMessage,
+    loggedInUserInfo,
+    getENSNames,
+    chatMentionCandidates,
+  } = input;
   const threadCreatedFromMessage = sourceMessage.threadCreatedFromMessage;
   if (threadCreatedFromMessage) {
     return threadCreatedFromMessage;
   }
 
   if (!loggedInUserInfo) {
     return null;
   }
 
   const { messageInfo, threadInfo } = sourceMessage;
   return await createPendingSidebar({
     sourceMessageInfo: messageInfo,
     parentThreadInfo: threadInfo,
     loggedInUserInfo,
-    markdownRules: getDefaultTextMessageRules().simpleMarkdownRules,
+    markdownRules: getDefaultTextMessageRules(chatMentionCandidates)
+      .simpleMarkdownRules,
     getENSNames,
   });
 }
 
 function useNavigateToSidebar(
   item: ChatMessageInfoItemWithHeight,
 ): () => mixed {
   const loggedInUserInfo = useLoggedInUserInfo();
   const navigateToThread = useNavigateToThread();
   const cacheContext = React.useContext(ENSCacheContext);
+  const chatMentionCandidates = useThreadChatMentionCandidates(item.threadInfo);
   const { getENSNames } = cacheContext;
   return React.useCallback(async () => {
     const threadInfo = await getSidebarThreadInfo({
       sourceMessage: item,
       loggedInUserInfo,
       getENSNames,
+      chatMentionCandidates,
     });
     invariant(threadInfo, 'threadInfo should be set');
     navigateToThread({ threadInfo });
-  }, [navigateToThread, item, loggedInUserInfo, getENSNames]);
+  }, [
+    item,
+    loggedInUserInfo,
+    getENSNames,
+    chatMentionCandidates,
+    navigateToThread,
+  ]);
 }
 
 function useAnimatedNavigateToSidebar(
   item: ChatMessageInfoItemWithHeight,
 ): () => void {
   const chatContext = React.useContext(ChatContext);
   const setSidebarSourceID = chatContext?.setCurrentTransitionSidebarSourceID;
   const navigateToSidebar = useNavigateToSidebar(item);
   const messageID = item.messageInfo.id;
   return React.useCallback(() => {
     setSidebarSourceID && setSidebarSourceID(messageID);
     navigateToSidebar();
   }, [setSidebarSourceID, messageID, navigateToSidebar]);
 }
 
 export {
   getUnresolvedSidebarThreadInfo,
   useNavigateToSidebar,
   useAnimatedNavigateToSidebar,
 };
diff --git a/native/chat/utils.js b/native/chat/utils.js
index 8a8061d5a..2cb3e6588 100644
--- a/native/chat/utils.js
+++ b/native/chat/utils.js
@@ -1,436 +1,447 @@
 // @flow
 
 import invariant from 'invariant';
 import * as React from 'react';
 import Animated from 'react-native-reanimated';
 
 import { useLoggedInUserInfo } from 'lib/hooks/account-hooks.js';
 import { colorIsDark } from 'lib/shared/color-utils.js';
 import { messageKey } from 'lib/shared/message-utils.js';
-import { viewerIsMember } from 'lib/shared/thread-utils.js';
+import {
+  viewerIsMember,
+  useThreadChatMentionCandidates,
+} from 'lib/shared/thread-utils.js';
 import type { ThreadInfo } from 'lib/types/thread-types.js';
 
 import { clusterEndHeight } from './chat-constants.js';
 import { ChatContext, useHeightMeasurer } from './chat-context.js';
 import { failedSendHeight } from './failed-send.react.js';
 import {
   useNativeMessageListData,
   type NativeChatMessageItem,
 } from './message-data.react.js';
 import { authorNameHeight } from './message-header.react.js';
 import { multimediaMessageItemHeight } from './multimedia-message-utils.js';
 import { getUnresolvedSidebarThreadInfo } from './sidebar-navigation.js';
 import textMessageSendFailed from './text-message-send-failed.js';
 import { timestampHeight } from './timestamp.react.js';
 import { KeyboardContext } from '../keyboard/keyboard-state.js';
 import { OverlayContext } from '../navigation/overlay-context.js';
 import {
   MultimediaMessageTooltipModalRouteName,
   RobotextMessageTooltipModalRouteName,
   TextMessageTooltipModalRouteName,
 } from '../navigation/route-names.js';
 import type {
   ChatMessageInfoItemWithHeight,
   ChatMessageItemWithHeight,
   ChatTextMessageInfoItemWithHeight,
 } from '../types/chat-types.js';
 import type {
   LayoutCoordinates,
   VerticalBounds,
 } from '../types/layout-types.js';
 import type { AnimatedViewStyle } from '../types/styles.js';
 
 /* eslint-disable import/no-named-as-default-member */
 const {
   Node,
   Extrapolate,
   interpolateNode,
   interpolateColors,
   block,
   call,
   eq,
   cond,
   sub,
 } = Animated;
 /* eslint-enable import/no-named-as-default-member */
 
 function textMessageItemHeight(
   item: ChatTextMessageInfoItemWithHeight,
 ): number {
   const { messageInfo, contentHeight, startsCluster, endsCluster } = item;
   const { isViewer } = messageInfo.creator;
   let height = 5 + contentHeight; // 5 from marginBottom in ComposedMessage
   if (!isViewer && startsCluster) {
     height += authorNameHeight;
   }
   if (endsCluster) {
     height += clusterEndHeight;
   }
   if (textMessageSendFailed(item)) {
     height += failedSendHeight;
   }
 
   return height;
 }
 
 function messageItemHeight(item: ChatMessageInfoItemWithHeight): number {
   let height = 0;
   if (item.messageShapeType === 'text') {
     height += textMessageItemHeight(item);
   } else if (item.messageShapeType === 'multimedia') {
     height += multimediaMessageItemHeight(item);
   } else {
     height += item.contentHeight;
   }
   if (item.startsConversation) {
     height += timestampHeight;
   }
   return height;
 }
 
 function chatMessageItemHeight(item: ChatMessageItemWithHeight): number {
   if (item.itemType === 'loader') {
     return 56;
   }
   return messageItemHeight(item);
 }
 
 function useMessageTargetParameters(
   sourceMessage: ChatMessageInfoItemWithHeight,
   initialCoordinates: LayoutCoordinates,
   messageListVerticalBounds: VerticalBounds,
   currentInputBarHeight: number,
   targetInputBarHeight: number,
   sidebarThreadInfo: ?ThreadInfo,
 ): {
   +position: number,
   +color: string,
 } {
   const messageListData = useNativeMessageListData({
     searching: false,
     userInfoInputArray: [],
     threadInfo: sidebarThreadInfo,
   });
 
   const [messagesWithHeight, setMessagesWithHeight] =
     React.useState<?$ReadOnlyArray<ChatMessageItemWithHeight>>(null);
   const measureMessages = useHeightMeasurer();
 
   React.useEffect(() => {
     if (messageListData) {
       measureMessages(
         messageListData,
         sidebarThreadInfo,
         setMessagesWithHeight,
       );
     }
   }, [measureMessages, messageListData, sidebarThreadInfo]);
 
   const sourceMessageID = sourceMessage.messageInfo?.id;
   const targetDistanceFromBottom = React.useMemo(() => {
     if (!messagesWithHeight) {
       return 0;
     }
 
     let offset = 0;
     for (const message of messagesWithHeight) {
       offset += chatMessageItemHeight(message);
       if (message.messageInfo && message.messageInfo.id === sourceMessageID) {
         return offset;
       }
     }
 
     return (
       messageListVerticalBounds.height + chatMessageItemHeight(sourceMessage)
     );
   }, [
     messageListVerticalBounds.height,
     messagesWithHeight,
     sourceMessage,
     sourceMessageID,
   ]);
 
   if (!sidebarThreadInfo) {
     return {
       position: 0,
       color: sourceMessage.threadInfo.color,
     };
   }
 
   const authorNameComponentHeight = sourceMessage.messageInfo.creator.isViewer
     ? 0
     : authorNameHeight;
   const currentDistanceFromBottom =
     messageListVerticalBounds.height +
     messageListVerticalBounds.y -
     initialCoordinates.y +
     timestampHeight +
     authorNameComponentHeight +
     currentInputBarHeight;
   return {
     position:
       targetDistanceFromBottom +
       targetInputBarHeight -
       currentDistanceFromBottom,
     color: sidebarThreadInfo.color,
   };
 }
 
 type AnimatedMessageArgs = {
   +sourceMessage: ChatMessageInfoItemWithHeight,
   +initialCoordinates: LayoutCoordinates,
   +messageListVerticalBounds: VerticalBounds,
   +progress: Node,
   +targetInputBarHeight: ?number,
 };
 
 function useAnimatedMessageTooltipButton({
   sourceMessage,
   initialCoordinates,
   messageListVerticalBounds,
   progress,
   targetInputBarHeight,
 }: AnimatedMessageArgs): {
   +style: AnimatedViewStyle,
   +threadColorOverride: ?Node,
   +isThreadColorDarkOverride: ?boolean,
 } {
   const chatContext = React.useContext(ChatContext);
   invariant(chatContext, 'chatContext should be set');
   const {
     currentTransitionSidebarSourceID,
     setCurrentTransitionSidebarSourceID,
     chatInputBarHeights,
     sidebarAnimationType,
     setSidebarAnimationType,
   } = chatContext;
 
   const loggedInUserInfo = useLoggedInUserInfo();
+  const chatMentionCandidates = useThreadChatMentionCandidates(
+    sourceMessage.threadInfo,
+  );
   const sidebarThreadInfo = React.useMemo(
-    () => getUnresolvedSidebarThreadInfo({ sourceMessage, loggedInUserInfo }),
-    [sourceMessage, loggedInUserInfo],
+    () =>
+      getUnresolvedSidebarThreadInfo({
+        sourceMessage,
+        loggedInUserInfo,
+        chatMentionCandidates,
+      }),
+    [sourceMessage, loggedInUserInfo, chatMentionCandidates],
   );
 
   const currentInputBarHeight =
     chatInputBarHeights.get(sourceMessage.threadInfo.id) ?? 0;
   const keyboardState = React.useContext(KeyboardContext);
 
   const newSidebarAnimationType =
     !currentInputBarHeight ||
     !targetInputBarHeight ||
     keyboardState?.keyboardShowing ||
     !viewerIsMember(sidebarThreadInfo)
       ? 'fade_source_message'
       : 'move_source_message';
   React.useEffect(() => {
     setSidebarAnimationType(newSidebarAnimationType);
   }, [setSidebarAnimationType, newSidebarAnimationType]);
 
   const { position: targetPosition, color: targetColor } =
     useMessageTargetParameters(
       sourceMessage,
       initialCoordinates,
       messageListVerticalBounds,
       currentInputBarHeight,
       targetInputBarHeight ?? currentInputBarHeight,
       sidebarThreadInfo,
     );
 
   React.useEffect(() => {
     return () => setCurrentTransitionSidebarSourceID(null);
   }, [setCurrentTransitionSidebarSourceID]);
 
   const bottom = React.useMemo(
     () =>
       interpolateNode(progress, {
         inputRange: [0.3, 1],
         outputRange: [targetPosition, 0],
         extrapolate: Extrapolate.CLAMP,
       }),
     [progress, targetPosition],
   );
 
   const [isThreadColorDarkOverride, setThreadColorDarkOverride] =
     React.useState<?boolean>(null);
   const setThreadColorBrightness = React.useCallback(() => {
     const isSourceThreadDark = colorIsDark(sourceMessage.threadInfo.color);
     const isTargetThreadDark = colorIsDark(targetColor);
     if (isSourceThreadDark !== isTargetThreadDark) {
       setThreadColorDarkOverride(isTargetThreadDark);
     }
   }, [sourceMessage.threadInfo.color, targetColor]);
 
   const threadColorOverride = React.useMemo(() => {
     if (
       sourceMessage.messageShapeType !== 'text' ||
       !currentTransitionSidebarSourceID
     ) {
       return null;
     }
     return block([
       cond(eq(progress, 1), call([], setThreadColorBrightness)),
       interpolateColors(progress, {
         inputRange: [0, 1],
         outputColorRange: [
           `#${targetColor}`,
           `#${sourceMessage.threadInfo.color}`,
         ],
       }),
     ]);
   }, [
     currentTransitionSidebarSourceID,
     progress,
     setThreadColorBrightness,
     sourceMessage.messageShapeType,
     sourceMessage.threadInfo.color,
     targetColor,
   ]);
 
   const messageContainerStyle = React.useMemo(() => {
     return {
       bottom: currentTransitionSidebarSourceID ? bottom : 0,
       opacity:
         currentTransitionSidebarSourceID &&
         sidebarAnimationType === 'fade_source_message'
           ? 0
           : 1,
     };
   }, [bottom, currentTransitionSidebarSourceID, sidebarAnimationType]);
 
   return {
     style: messageContainerStyle,
     threadColorOverride,
     isThreadColorDarkOverride,
   };
 }
 
 function getMessageTooltipKey(item: ChatMessageInfoItemWithHeight): string {
   return `tooltip|${messageKey(item.messageInfo)}`;
 }
 
 function isMessageTooltipKey(key: string): boolean {
   return key.startsWith('tooltip|');
 }
 
 function useOverlayPosition(item: ChatMessageInfoItemWithHeight) {
   const overlayContext = React.useContext(OverlayContext);
   invariant(overlayContext, 'should be set');
 
   for (const overlay of overlayContext.visibleOverlays) {
     if (
       (overlay.routeName === MultimediaMessageTooltipModalRouteName ||
         overlay.routeName === TextMessageTooltipModalRouteName ||
         overlay.routeName === RobotextMessageTooltipModalRouteName) &&
       overlay.routeKey === getMessageTooltipKey(item)
     ) {
       return overlay.position;
     }
   }
   return undefined;
 }
 
 function useContentAndHeaderOpacity(
   item: ChatMessageInfoItemWithHeight,
 ): number | Node {
   const overlayPosition = useOverlayPosition(item);
   const chatContext = React.useContext(ChatContext);
   return React.useMemo(
     () =>
       overlayPosition &&
       chatContext?.sidebarAnimationType === 'move_source_message'
         ? sub(
             1,
             interpolateNode(overlayPosition, {
               inputRange: [0.05, 0.06],
               outputRange: [0, 1],
               extrapolate: Extrapolate.CLAMP,
             }),
           )
         : 1,
     [chatContext?.sidebarAnimationType, overlayPosition],
   );
 }
 
 function useDeliveryIconOpacity(
   item: ChatMessageInfoItemWithHeight,
 ): number | Node {
   const overlayPosition = useOverlayPosition(item);
   const chatContext = React.useContext(ChatContext);
   return React.useMemo(() => {
     if (
       !overlayPosition ||
       !chatContext?.currentTransitionSidebarSourceID ||
       chatContext?.sidebarAnimationType === 'fade_source_message'
     ) {
       return 1;
     }
     return interpolateNode(overlayPosition, {
       inputRange: [0.05, 0.06, 1],
       outputRange: [1, 0, 0],
       extrapolate: Extrapolate.CLAMP,
     });
   }, [
     chatContext?.currentTransitionSidebarSourceID,
     chatContext?.sidebarAnimationType,
     overlayPosition,
   ]);
 }
 
 function chatMessageItemKey(
   item: ChatMessageItemWithHeight | NativeChatMessageItem,
 ): string {
   if (item.itemType === 'loader') {
     return 'loader';
   }
   return messageKey(item.messageInfo);
 }
 
 function modifyItemForResultScreen(
   item: ChatMessageInfoItemWithHeight,
 ): ChatMessageInfoItemWithHeight {
   if (item.messageShapeType === 'robotext') {
     return item;
   }
 
   if (item.messageShapeType === 'multimedia') {
     return {
       ...item,
       startsConversation: false,
       startsCluster: true,
       endsCluster: true,
       messageInfo: {
         ...item.messageInfo,
         creator: {
           ...item.messageInfo.creator,
           isViewer: false,
         },
       },
     };
   }
 
   return {
     ...item,
     startsConversation: false,
     startsCluster: true,
     endsCluster: true,
     messageInfo: {
       ...item.messageInfo,
       creator: {
         ...item.messageInfo.creator,
         isViewer: false,
       },
     },
   };
 }
 
 export {
   chatMessageItemKey,
   chatMessageItemHeight,
   useAnimatedMessageTooltipButton,
   messageItemHeight,
   getMessageTooltipKey,
   isMessageTooltipKey,
   useContentAndHeaderOpacity,
   useDeliveryIconOpacity,
   modifyItemForResultScreen,
 };
diff --git a/native/markdown/rules.react.js b/native/markdown/rules.react.js
index 595ba0e41..ab4b2afab 100644
--- a/native/markdown/rules.react.js
+++ b/native/markdown/rules.react.js
@@ -1,411 +1,422 @@
 // @flow
 
 import _memoize from 'lodash/memoize.js';
 import * as React from 'react';
 import { Text, View, Platform } from 'react-native';
 import * as SimpleMarkdown from 'simple-markdown';
 
 import * as SharedMarkdown from 'lib/shared/markdown.js';
-import type { RelativeMemberInfo, ThreadInfo } from 'lib/types/thread-types.js';
+import type {
+  RelativeMemberInfo,
+  ThreadInfo,
+  ChatMentionCandidates,
+} from 'lib/types/thread-types.js';
 
 import MarkdownLink from './markdown-link.react.js';
 import MarkdownParagraph from './markdown-paragraph.react.js';
 import MarkdownSpoiler from './markdown-spoiler.react.js';
 import { getMarkdownStyles } from './styles.js';
 
 export type MarkdownRules = {
   +simpleMarkdownRules: SharedMarkdown.ParserRules,
   +emojiOnlyFactor: ?number,
   // We need to use a Text container for Entry because it needs to match up
   // exactly with TextInput. However, if we use a Text container, we can't
   // support styles for things like blockQuote, which rely on rendering as a
   // View, and Views can't be nested inside Texts without explicit height and
   // width
   +container: 'View' | 'Text',
 };
 
 // Entry requires a seamless transition between Markdown and TextInput
 // components, so we can't do anything that would change the position of text
 const inlineMarkdownRules: boolean => MarkdownRules = _memoize(useDarkStyle => {
   const styles = getMarkdownStyles(useDarkStyle ? 'dark' : 'light');
   const simpleMarkdownRules = {
     // Matches 'https://google.com' during parse phase and returns a 'link' node
     url: {
       ...SimpleMarkdown.defaultRules.url,
       // simple-markdown is case-sensitive, but we don't want to be
       match: SimpleMarkdown.inlineRegex(SharedMarkdown.urlRegex),
     },
     // Matches '[Google](https://google.com)' during parse phase and handles
     // rendering all 'link' nodes, including for 'autolink' and 'url'
     link: {
       ...SimpleMarkdown.defaultRules.link,
       match: () => null,
       react(
         node: SharedMarkdown.SingleASTNode,
         output: SharedMarkdown.Output<SharedMarkdown.ReactElement>,
         state: SharedMarkdown.State,
       ) {
         return (
           <MarkdownLink
             key={state.key}
             style={styles.link}
             target={node.target}
           >
             {output(node.content, state)}
           </MarkdownLink>
         );
       },
     },
     // Each line gets parsed into a 'paragraph' node. The AST returned by the
     // parser will be an array of one or more 'paragraph' nodes
     paragraph: {
       ...SimpleMarkdown.defaultRules.paragraph,
       // simple-markdown's default RegEx collapses multiple newlines into one.
       // We want to keep the newlines, but when rendering within a View, we
       // strip just one trailing newline off, since the View adds vertical
       // spacing between its children
       match: (source: string, state: SharedMarkdown.State) => {
         if (state.inline) {
           return null;
         } else if (state.container === 'View') {
           return SharedMarkdown.paragraphStripTrailingNewlineRegex.exec(source);
         } else {
           return SharedMarkdown.paragraphRegex.exec(source);
         }
       },
       parse(
         capture: SharedMarkdown.Capture,
         parse: SharedMarkdown.Parser,
         state: SharedMarkdown.State,
       ) {
         let content = capture[1];
         if (state.container === 'View') {
           // React Native renders empty lines with less height. We want to
           // preserve the newline characters, so we replace empty lines with a
           // single space
           content = content.replace(/^$/m, ' ');
         }
         return {
           content: SimpleMarkdown.parseInline(parse, content, state),
         };
       },
       // eslint-disable-next-line react/display-name
       react: (
         node: SharedMarkdown.SingleASTNode,
         output: SharedMarkdown.Output<SharedMarkdown.ReactElement>,
         state: SharedMarkdown.State,
       ) => (
         <MarkdownParagraph key={state.key} style={state.textStyle}>
           {output(node.content, state)}
         </MarkdownParagraph>
       ),
     },
     // This is the leaf node in the AST returned by the parse phase
     text: SimpleMarkdown.defaultRules.text,
   };
   return {
     simpleMarkdownRules,
     emojiOnlyFactor: null,
     container: 'Text',
   };
 });
 
 // We allow the most markdown features for TextMessage, which doesn't have the
 // same requirements as Entry
 const fullMarkdownRules: boolean => MarkdownRules = _memoize(useDarkStyle => {
   const styles = getMarkdownStyles(useDarkStyle ? 'dark' : 'light');
   const inlineRules = inlineMarkdownRules(useDarkStyle);
   const simpleMarkdownRules = {
     ...inlineRules.simpleMarkdownRules,
     // Matches '<https://google.com>' during parse phase and returns a 'link'
     // node
     autolink: SimpleMarkdown.defaultRules.autolink,
     // Matches '[Google](https://google.com)' during parse phase and handles
     // rendering all 'link' nodes, including for 'autolink' and 'url'
     link: {
       ...inlineRules.simpleMarkdownRules.link,
       match: SimpleMarkdown.defaultRules.link.match,
     },
     mailto: SimpleMarkdown.defaultRules.mailto,
     em: {
       ...SimpleMarkdown.defaultRules.em,
       // eslint-disable-next-line react/display-name
       react: (
         node: SharedMarkdown.SingleASTNode,
         output: SharedMarkdown.Output<SharedMarkdown.ReactElement>,
         state: SharedMarkdown.State,
       ) => (
         <Text key={state.key} style={styles.italics}>
           {output(node.content, state)}
         </Text>
       ),
     },
     strong: {
       ...SimpleMarkdown.defaultRules.strong,
       // eslint-disable-next-line react/display-name
       react: (
         node: SharedMarkdown.SingleASTNode,
         output: SharedMarkdown.Output<SharedMarkdown.ReactElement>,
         state: SharedMarkdown.State,
       ) => (
         <Text key={state.key} style={styles.bold}>
           {output(node.content, state)}
         </Text>
       ),
     },
     u: {
       ...SimpleMarkdown.defaultRules.u,
       // eslint-disable-next-line react/display-name
       react: (
         node: SharedMarkdown.SingleASTNode,
         output: SharedMarkdown.Output<SharedMarkdown.ReactElement>,
         state: SharedMarkdown.State,
       ) => (
         <Text key={state.key} style={styles.underline}>
           {output(node.content, state)}
         </Text>
       ),
     },
     del: {
       ...SimpleMarkdown.defaultRules.del,
       // eslint-disable-next-line react/display-name
       react: (
         node: SharedMarkdown.SingleASTNode,
         output: SharedMarkdown.Output<SharedMarkdown.ReactElement>,
         state: SharedMarkdown.State,
       ) => (
         <Text key={state.key} style={styles.strikethrough}>
           {output(node.content, state)}
         </Text>
       ),
     },
     spoiler: {
       order: SimpleMarkdown.defaultRules.paragraph.order - 1,
       match: SimpleMarkdown.inlineRegex(SharedMarkdown.spoilerRegex),
       parse(
         capture: SharedMarkdown.Capture,
         parse: SharedMarkdown.Parser,
         state: SharedMarkdown.State,
       ) {
         const content = capture[1];
         return {
           content: SimpleMarkdown.parseInline(parse, content, state),
         };
       },
       // eslint-disable-next-line react/display-name
       react: (
         node: SharedMarkdown.SingleASTNode,
         output: SharedMarkdown.Output<SharedMarkdown.ReactElement>,
         state: SharedMarkdown.State,
       ) => (
         <MarkdownSpoiler
           key={state.key}
           spoilerIdentifier={state.key}
           text={output(node.content, state)}
         />
       ),
     },
     inlineCode: {
       ...SimpleMarkdown.defaultRules.inlineCode,
       // eslint-disable-next-line react/display-name
       react: (
         node: SharedMarkdown.SingleASTNode,
         output: SharedMarkdown.Output<SharedMarkdown.ReactElement>,
         state: SharedMarkdown.State,
       ) => (
         <Text key={state.key} style={styles.inlineCode}>
           {node.content}
         </Text>
       ),
     },
     heading: {
       ...SimpleMarkdown.defaultRules.heading,
       match: SimpleMarkdown.blockRegex(
         SharedMarkdown.headingStripFollowingNewlineRegex,
       ),
       // eslint-disable-next-line react/display-name
       react(
         node: SharedMarkdown.SingleASTNode,
         output: SharedMarkdown.Output<SharedMarkdown.ReactElement>,
         state: SharedMarkdown.State,
       ) {
         const headingStyle = styles['h' + node.level];
         return (
           <Text key={state.key} style={[state.textStyle, headingStyle]}>
             {output(node.content, state)}
           </Text>
         );
       },
     },
     blockQuote: {
       ...SimpleMarkdown.defaultRules.blockQuote,
       // match end of blockQuote by either \n\n or end of string
       match: SharedMarkdown.matchBlockQuote(
         SharedMarkdown.blockQuoteStripFollowingNewlineRegex,
       ),
       parse: SharedMarkdown.parseBlockQuote,
       // eslint-disable-next-line react/display-name
       react: (
         node: SharedMarkdown.SingleASTNode,
         output: SharedMarkdown.Output<SharedMarkdown.ReactElement>,
         state: SharedMarkdown.State,
       ) => {
         const { isNestedQuote } = state;
         const backgroundColor = isNestedQuote ? '#00000000' : '#00000066';
         const borderLeftColor = (Platform.select({
           ios: '#00000066',
           default: isNestedQuote ? '#00000066' : '#000000A3',
         }): string);
 
         return (
           <View
             key={state.key}
             style={[styles.blockQuote, { backgroundColor, borderLeftColor }]}
           >
             {output(node.content, { ...state, isNestedQuote: true })}
           </View>
         );
       },
     },
     codeBlock: {
       ...SimpleMarkdown.defaultRules.codeBlock,
       match: SimpleMarkdown.blockRegex(
         SharedMarkdown.codeBlockStripTrailingNewlineRegex,
       ),
       parse(capture: SharedMarkdown.Capture) {
         return {
           content: capture[1].replace(/^ {4}/gm, ''),
         };
       },
       // eslint-disable-next-line react/display-name
       react: (
         node: SharedMarkdown.SingleASTNode,
         output: SharedMarkdown.Output<SharedMarkdown.ReactElement>,
         state: SharedMarkdown.State,
       ) => (
         <View key={state.key} style={styles.codeBlock}>
           <Text style={[state.textStyle, styles.codeBlockText]}>
             {node.content}
           </Text>
         </View>
       ),
     },
     fence: {
       ...SimpleMarkdown.defaultRules.fence,
       match: SimpleMarkdown.blockRegex(
         SharedMarkdown.fenceStripTrailingNewlineRegex,
       ),
       parse: (capture: SharedMarkdown.Capture) => ({
         type: 'codeBlock',
         content: capture[2],
       }),
     },
     json: {
       order: SimpleMarkdown.defaultRules.paragraph.order - 1,
       match: (source: string, state: SharedMarkdown.State) => {
         if (state.inline) {
           return null;
         }
         return SharedMarkdown.jsonMatch(source);
       },
       parse: (capture: SharedMarkdown.Capture) => {
         const jsonCapture: SharedMarkdown.JSONCapture = (capture: any);
         return {
           type: 'codeBlock',
           content: SharedMarkdown.jsonPrint(jsonCapture),
         };
       },
     },
     list: {
       ...SimpleMarkdown.defaultRules.list,
       match: SharedMarkdown.matchList,
       parse: SharedMarkdown.parseList,
       react(
         node: SharedMarkdown.SingleASTNode,
         output: SharedMarkdown.Output<SharedMarkdown.ReactElement>,
         state: SharedMarkdown.State,
       ) {
         const children = node.items.map((item, i) => {
           const content = output(item, state);
           const bulletValue = node.ordered ? node.start + i + '. ' : '\u2022 ';
           return (
             <View key={i} style={styles.listRow}>
               <Text style={[state.textStyle, styles.listBulletStyle]}>
                 {bulletValue}
               </Text>
               <View style={styles.insideListView}>{content}</View>
             </View>
           );
         });
 
         return <View key={state.key}>{children}</View>;
       },
     },
     escape: SimpleMarkdown.defaultRules.escape,
   };
   return {
     ...inlineRules,
     simpleMarkdownRules,
     emojiOnlyFactor: 2,
     container: 'View',
   };
 });
 
 function useTextMessageRulesFunc(
   threadInfo: ThreadInfo,
+  chatMentionCandidates: ChatMentionCandidates,
 ): (useDarkStyle: boolean) => MarkdownRules {
   const { members } = threadInfo;
   return React.useMemo(
     () =>
       _memoize<[boolean], MarkdownRules>((useDarkStyle: boolean) =>
-        textMessageRules(members, useDarkStyle),
+        textMessageRules(members, chatMentionCandidates, useDarkStyle),
       ),
-    [members],
+    [members, chatMentionCandidates],
   );
 }
 
 function textMessageRules(
   members: $ReadOnlyArray<RelativeMemberInfo>,
+  chatMentionCandidates: ChatMentionCandidates,
   useDarkStyle: boolean,
 ): MarkdownRules {
   const styles = getMarkdownStyles(useDarkStyle ? 'dark' : 'light');
   const baseRules = fullMarkdownRules(useDarkStyle);
   return {
     ...baseRules,
     simpleMarkdownRules: {
       ...baseRules.simpleMarkdownRules,
       mention: {
         ...SimpleMarkdown.defaultRules.strong,
         match: SharedMarkdown.matchMentions(members),
         parse: (capture: SharedMarkdown.Capture) => ({
           content: capture[0],
         }),
         // eslint-disable-next-line react/display-name
         react: (
           node: SharedMarkdown.SingleASTNode,
           output: SharedMarkdown.Output<SharedMarkdown.ReactElement>,
           state: SharedMarkdown.State,
         ) => (
           <Text key={state.key} style={styles.bold}>
             {node.content}
           </Text>
         ),
       },
     },
   };
 }
 
 let defaultTextMessageRules = null;
 
-function getDefaultTextMessageRules(): MarkdownRules {
+function getDefaultTextMessageRules(
+  overrideDefaultChatMentionCandidates: ChatMentionCandidates = {},
+): MarkdownRules {
+  if (Object.keys(overrideDefaultChatMentionCandidates).length > 0) {
+    return textMessageRules([], overrideDefaultChatMentionCandidates, false);
+  }
   if (!defaultTextMessageRules) {
-    defaultTextMessageRules = textMessageRules([], false);
+    defaultTextMessageRules = textMessageRules([], {}, false);
   }
   return defaultTextMessageRules;
 }
 
 export {
   inlineMarkdownRules,
   useTextMessageRulesFunc,
   getDefaultTextMessageRules,
 };