diff --git a/lib/shared/markdown.js b/lib/shared/markdown.js
index 7bab982fa..ad5e361dd 100644
--- a/lib/shared/markdown.js
+++ b/lib/shared/markdown.js
@@ -1,239 +1,272 @@
 // @flow
 
 import invariant from 'invariant';
 
 import type { RelativeMemberInfo } from '../types/thread-types';
 import { oldValidUsernameRegexString } from './account-utils';
 
 // simple-markdown types
 export type State = {
   key?: string | number | void,
   inline?: ?boolean,
   [string]: any,
 };
 
 export type Parser = (source: string, state?: ?State) => Array<SingleASTNode>;
 
 export type Capture =
   | (Array<string> & { +index: number, ... })
   | (Array<string> & { +index?: number, ... });
 
 export type SingleASTNode = {
   type: string,
   [string]: any,
 };
 
 export type ASTNode = SingleASTNode | Array<SingleASTNode>;
 
 type UnTypedASTNode = {
   [string]: any,
   ...
 };
 
 type MatchFunction = { regex?: RegExp, ... } & ((
   source: string,
   state: State,
   prevCapture: string,
 ) => ?Capture);
 
 export type ReactElement = React$Element<any>;
 type ReactElements = React$Node;
 
 export type Output<Result> = (node: ASTNode, state?: ?State) => Result;
 
 type ArrayNodeOutput<Result> = (
   node: Array<SingleASTNode>,
   nestedOutput: Output<Result>,
   state: State,
 ) => Result;
 
 type ArrayRule = {
   +react?: ArrayNodeOutput<ReactElements>,
   +html?: ArrayNodeOutput<string>,
   +[string]: ArrayNodeOutput<any>,
 };
 
 type ParseFunction = (
   capture: Capture,
   nestedParse: Parser,
   state: State,
 ) => UnTypedASTNode | ASTNode;
 
 type ParserRule = {
   +order: number,
   +match: MatchFunction,
   +quality?: (capture: Capture, state: State, prevCapture: string) => number,
   +parse: ParseFunction,
   ...
 };
 
 export type ParserRules = {
   +Array?: ArrayRule,
   +[type: string]: ParserRule,
   ...
 };
 
 const paragraphRegex: RegExp = /^((?:[^\n]*)(?:\n|$))/;
 const paragraphStripTrailingNewlineRegex: RegExp = /^([^\n]*)(?:\n|$)/;
 
 const headingRegex: RegExp = /^ *(#{1,6}) ([^\n]+?)#* *(?![^\n])/;
 const headingStripFollowingNewlineRegex: RegExp = /^ *(#{1,6}) ([^\n]+?)#* *(?:\n|$)/;
 
 const fenceRegex: RegExp = /^(`{3,}|~{3,})[^\n]*\n([\s\S]*?\n)\1(?:\n|$)/;
 const fenceStripTrailingNewlineRegex: RegExp = /^(`{3,}|~{3,})[^\n]*\n([\s\S]*?)\n\1(?:\n|$)/;
 
 const codeBlockRegex: RegExp = /^(?: {4}[^\n]*\n*?)+(?!\n* {4}[^\n])(?:\n|$)/;
 const codeBlockStripTrailingNewlineRegex: RegExp = /^((?: {4}[^\n]*\n*?)+)(?!\n* {4}[^\n])(?:\n|$)/;
 
-const blockQuoteRegex: RegExp = /^( *>[^\n]+(?:\n[^\n]+)*)(?:\n|$)/;
-const blockQuoteStripFollowingNewlineRegex: RegExp = /^( *>[^\n]+(?:\n[^\n]+)*)(?:\n|$){2}/;
-
 const urlRegex: RegExp = /^(https?:\/\/[^\s<]+[^<.,:;"')\]\s])/i;
 
 const mentionRegex = new RegExp(`^(@(${oldValidUsernameRegexString}))\\b`);
 
 export type JSONCapture = Array<string> & {
   +json: Object,
   +index?: void,
   ...
 };
 function jsonMatch(source: string): ?JSONCapture {
   if (!source.startsWith('{')) {
     return null;
   }
 
   let jsonString = '';
   let counter = 0;
   for (let i = 0; i < source.length; i++) {
     const char = source[i];
     jsonString += char;
     if (char === '{') {
       counter++;
     } else if (char === '}') {
       counter--;
     }
     if (counter === 0) {
       break;
     }
   }
   if (counter !== 0) {
     return null;
   }
 
   let json;
   try {
     json = JSON.parse(jsonString);
   } catch {
     return null;
   }
   if (!json || typeof json !== 'object') {
     return null;
   }
 
   return { ...([jsonString]: any), json };
 }
 
 function jsonPrint(capture: JSONCapture): string {
   return JSON.stringify(capture.json, null, '  ');
 }
 
 const listRegex = /^( *)([*+-]|\d+\.) ([\s\S]+?)(?:\n{2}|\s*\n*$)/;
 const listItemRegex = /^( *)([*+-]|\d+\.) [^\n]*(?:\n(?!\1(?:[*+-]|\d+\.) )[^\n]*)*(\n|$)/gm;
 const listItemPrefixRegex = /^( *)([*+-]|\d+\.) /;
 const listLookBehindRegex = /(?:^|\n)( *)$/;
 
 function matchList(source: string, state: State): RegExp$matchResult | null {
   if (state.inline) {
     return null;
   }
   const prevCaptureStr = state.prevCapture ? state.prevCapture[0] : '';
   const isStartOfLineCapture = listLookBehindRegex.exec(prevCaptureStr);
   if (!isStartOfLineCapture) {
     return null;
   }
   const fullSource = isStartOfLineCapture[1] + source;
   return listRegex.exec(fullSource);
 }
 
 // We've defined our own parse function for lists because simple-markdown
 // handles newlines differently. Outside of that our implementation is fairly
 // similar. For more details about list parsing works, take a look at the
 // comments in the simple-markdown package
 function parseList(
   capture: Capture,
   parse: Parser,
   state: State,
 ): UnTypedASTNode {
   const bullet = capture[2];
   const ordered = bullet.length > 1;
   const start = ordered ? Number(bullet) : undefined;
   const items = capture[0].match(listItemRegex);
 
   let itemContent = null;
   if (items) {
     itemContent = items.map((item: string) => {
       const prefixCapture = listItemPrefixRegex.exec(item);
       const space = prefixCapture ? prefixCapture[0].length : 0;
       const spaceRegex = new RegExp('^ {1,' + space + '}', 'gm');
       const content: string = item
         .replace(spaceRegex, '')
         .replace(listItemPrefixRegex, '');
       // We're handling this different than simple-markdown -
       // each item is a paragraph
       return parse(content, state);
     });
   }
 
   return {
     ordered: ordered,
     start: start,
     items: itemContent,
   };
 }
 
 function matchMentions(
   members: $ReadOnlyArray<RelativeMemberInfo>,
 ): MatchFunction {
   const memberSet = new Set(
     members
       .filter(({ role }) => role)
       .map(({ username }) => username?.toLowerCase())
       .filter(Boolean),
   );
   const match = (source: string, state: State) => {
     if (!state.inline) {
       return null;
     }
     const result = mentionRegex.exec(source);
     if (!result) {
       return null;
     }
     const username = result[2];
     invariant(username, 'mentionRegex should match two capture groups');
     if (!memberSet.has(username.toLowerCase())) {
       return null;
     }
     return result;
   };
   match.regex = mentionRegex;
   return match;
 }
 
+const blockQuoteRegex: RegExp = /^( *>[^\n]+(?:\n[^\n]+)*)(?:\n|$)/;
+const blockQuoteStripFollowingNewlineRegex: RegExp = /^( *>[^\n]+(?:\n[^\n]+)*)(?:\n|$){2}/;
+const maxNestedQuotations = 5;
+
+// Custom match and parse functions implementation for block quotes
+// to allow us to specify quotes parsing depth
+// to avoid too many recursive calls and e.g. app crash
+function matchBlockQuote(quoteRegex: RegExp): MatchFunction {
+  return (source: string, state: State) => {
+    if (
+      state.inline ||
+      (state?.quotationsDepth && state.quotationsDepth >= maxNestedQuotations)
+    ) {
+      return null;
+    }
+    return quoteRegex.exec(source);
+  };
+}
+
+function parseBlockQuote(
+  capture: Capture,
+  parse: Parser,
+  state: State,
+): UnTypedASTNode {
+  const content = capture[1].replace(/^ *> ?/gm, '');
+  const currentQuotationsDepth = state?.quotationsDepth ?? 0;
+  return {
+    content: parse(content, {
+      ...state,
+      quotationsDepth: currentQuotationsDepth + 1,
+    }),
+  };
+}
+
 export {
   paragraphRegex,
   paragraphStripTrailingNewlineRegex,
   urlRegex,
   blockQuoteRegex,
   blockQuoteStripFollowingNewlineRegex,
   headingRegex,
   headingStripFollowingNewlineRegex,
   codeBlockRegex,
   codeBlockStripTrailingNewlineRegex,
   fenceRegex,
   fenceStripTrailingNewlineRegex,
+  matchBlockQuote,
+  parseBlockQuote,
   jsonMatch,
   jsonPrint,
   matchList,
   parseList,
   matchMentions,
 };
diff --git a/native/markdown/rules.react.js b/native/markdown/rules.react.js
index 7ddca1887..cf6cf7b97 100644
--- a/native/markdown/rules.react.js
+++ b/native/markdown/rules.react.js
@@ -1,392 +1,383 @@
 // @flow
 
 import _memoize from 'lodash/memoize';
 import * as React from 'react';
 import { Text, View } from 'react-native';
 import { createSelector } from 'reselect';
 import * as SimpleMarkdown from 'simple-markdown';
 
 import { relativeMemberInfoSelectorForMembersOfThread } from 'lib/selectors/user-selectors';
 import * as SharedMarkdown from 'lib/shared/markdown';
 import type { RelativeMemberInfo } from 'lib/types/thread-types';
 
 import { useSelector } from '../redux/redux-utils';
 import MarkdownLink from './markdown-link.react';
 import { getMarkdownStyles } from './styles';
 
 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,
       ) => (
         <Text key={state.key} style={state.textStyle}>
           {output(node.content, state)}
         </Text>
       ),
     },
     // 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>
       ),
     },
     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: SimpleMarkdown.blockRegex(
+      match: SharedMarkdown.matchBlockQuote(
         SharedMarkdown.blockQuoteStripFollowingNewlineRegex,
       ),
-      parse(
-        capture: SharedMarkdown.Capture,
-        parse: SharedMarkdown.Parser,
-        state: SharedMarkdown.State,
-      ) {
-        const content = capture[1].replace(/^ *> ?/gm, '');
-        return {
-          content: parse(content, state),
-        };
-      },
+      parse: SharedMarkdown.parseBlockQuote,
       // 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.blockQuote}>
           {output(node.content, state)}
         </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(
   threadID: ?string,
 ): (useDarkStyle: boolean) => MarkdownRules {
   return useSelector(getTextMessageRulesFunction(threadID));
 }
 
 const getTextMessageRulesFunction = _memoize((threadID: ?string) =>
   createSelector(
     relativeMemberInfoSelectorForMembersOfThread(threadID),
     (
       threadMembers: $ReadOnlyArray<RelativeMemberInfo>,
     ): (boolean => MarkdownRules) => {
       if (!threadID) {
         return fullMarkdownRules;
       }
       return _memoize<[boolean], MarkdownRules>((useDarkStyle: boolean) =>
         textMessageRules(threadMembers, useDarkStyle),
       );
     },
   ),
 );
 
 function textMessageRules(
   members: $ReadOnlyArray<RelativeMemberInfo>,
   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 {
   if (!defaultTextMessageRules) {
     defaultTextMessageRules = textMessageRules([], false);
   }
   return defaultTextMessageRules;
 }
 
 export {
   inlineMarkdownRules,
   useTextMessageRulesFunc,
   getDefaultTextMessageRules,
 };
diff --git a/web/markdown/rules.react.js b/web/markdown/rules.react.js
index 03bdd1212..57b89b355 100644
--- a/web/markdown/rules.react.js
+++ b/web/markdown/rules.react.js
@@ -1,199 +1,190 @@
 // @flow
 
 import _memoize from 'lodash/memoize';
 import * as React from 'react';
 import * as SimpleMarkdown from 'simple-markdown';
 
 import { relativeMemberInfoSelectorForMembersOfThread } from 'lib/selectors/user-selectors';
 import * as SharedMarkdown from 'lib/shared/markdown';
 import type { RelativeMemberInfo } from 'lib/types/thread-types';
 
 import { useSelector } from '../redux/redux-utils';
 
 export type MarkdownRules = {
   +simpleMarkdownRules: SharedMarkdown.ParserRules,
   +useDarkStyle: boolean,
 };
 
 const linkRules: boolean => MarkdownRules = _memoize(useDarkStyle => {
   const simpleMarkdownRules = {
     // We are using default simple-markdown rules
     // For more details, look at native/markdown/rules.react
     link: {
       ...SimpleMarkdown.defaultRules.link,
       match: () => null,
       // eslint-disable-next-line react/display-name
       react: (
         node: SharedMarkdown.SingleASTNode,
         output: SharedMarkdown.Output<SharedMarkdown.ReactElement>,
         state: SharedMarkdown.State,
       ) => (
         <a
           href={SimpleMarkdown.sanitizeUrl(node.target)}
           key={state.key}
           title={node.title}
           target="_blank"
           rel="noopener noreferrer"
         >
           {output(node.content, state)}
         </a>
       ),
     },
     paragraph: {
       ...SimpleMarkdown.defaultRules.paragraph,
       match: SimpleMarkdown.blockRegex(SharedMarkdown.paragraphRegex),
       // eslint-disable-next-line react/display-name
       react: (
         node: SharedMarkdown.SingleASTNode,
         output: SharedMarkdown.Output<SharedMarkdown.ReactElement>,
         state: SharedMarkdown.State,
       ) => (
         <React.Fragment key={state.key}>
           {output(node.content, state)}
         </React.Fragment>
       ),
     },
     text: SimpleMarkdown.defaultRules.text,
     url: {
       ...SimpleMarkdown.defaultRules.url,
       match: SimpleMarkdown.inlineRegex(SharedMarkdown.urlRegex),
     },
   };
   return {
     simpleMarkdownRules: simpleMarkdownRules,
     useDarkStyle,
   };
 });
 
 const markdownRules: boolean => MarkdownRules = _memoize(useDarkStyle => {
   const linkMarkdownRules = linkRules(useDarkStyle);
 
   const simpleMarkdownRules = {
     ...linkMarkdownRules.simpleMarkdownRules,
     autolink: SimpleMarkdown.defaultRules.autolink,
     link: {
       ...linkMarkdownRules.simpleMarkdownRules.link,
       match: SimpleMarkdown.defaultRules.link.match,
     },
     blockQuote: {
       ...SimpleMarkdown.defaultRules.blockQuote,
       // match end of blockQuote by either \n\n or end of string
-      match: SimpleMarkdown.blockRegex(SharedMarkdown.blockQuoteRegex),
-      parse(
-        capture: SharedMarkdown.Capture,
-        parse: SharedMarkdown.Parser,
-        state: SharedMarkdown.State,
-      ) {
-        const content = capture[1].replace(/^ *> ?/gm, '');
-        return {
-          content: parse(content, state),
-        };
-      },
+      match: SharedMarkdown.matchBlockQuote(SharedMarkdown.blockQuoteRegex),
+      parse: SharedMarkdown.parseBlockQuote,
     },
     inlineCode: SimpleMarkdown.defaultRules.inlineCode,
     em: SimpleMarkdown.defaultRules.em,
     strong: SimpleMarkdown.defaultRules.strong,
     del: SimpleMarkdown.defaultRules.del,
     u: SimpleMarkdown.defaultRules.u,
     heading: {
       ...SimpleMarkdown.defaultRules.heading,
       match: SimpleMarkdown.blockRegex(SharedMarkdown.headingRegex),
     },
     mailto: SimpleMarkdown.defaultRules.mailto,
     codeBlock: {
       ...SimpleMarkdown.defaultRules.codeBlock,
       match: SimpleMarkdown.blockRegex(SharedMarkdown.codeBlockRegex),
       parse: (capture: SharedMarkdown.Capture) => ({
         content: capture[0].replace(/^ {4}/gm, ''),
       }),
     },
     fence: {
       ...SimpleMarkdown.defaultRules.fence,
       match: SimpleMarkdown.blockRegex(SharedMarkdown.fenceRegex),
       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,
     },
     escape: SimpleMarkdown.defaultRules.escape,
   };
   return {
     ...linkMarkdownRules,
     simpleMarkdownRules,
     useDarkStyle,
   };
 });
 
 function useTextMessageRulesFunc(
   threadID: ?string,
 ): ?(boolean) => MarkdownRules {
   const threadMembers = useSelector(
     relativeMemberInfoSelectorForMembersOfThread(threadID),
   );
   return React.useMemo(() => {
     if (!threadMembers) {
       return undefined;
     }
     return _memoize<[boolean], MarkdownRules>((useDarkStyle: boolean) =>
       textMessageRules(threadMembers, useDarkStyle),
     );
   }, [threadMembers]);
 }
 
 function textMessageRules(
   members: $ReadOnlyArray<RelativeMemberInfo>,
   useDarkStyle: boolean,
 ): MarkdownRules {
   const baseRules = markdownRules(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,
         ) => <strong key={state.key}>{node.content}</strong>,
       },
     },
   };
 }
 
 let defaultTextMessageRules = null;
 
 function getDefaultTextMessageRules(): MarkdownRules {
   if (!defaultTextMessageRules) {
     defaultTextMessageRules = textMessageRules([], false);
   }
   return defaultTextMessageRules;
 }
 
 export { linkRules, useTextMessageRulesFunc, getDefaultTextMessageRules };