diff --git a/lib/shared/reaction-utils.js b/lib/shared/reaction-utils.js
--- a/lib/shared/reaction-utils.js
+++ b/lib/shared/reaction-utils.js
@@ -18,7 +18,6 @@
 } from '../types/message-types.js';
 import type { ThreadInfo } from '../types/minimally-encoded-thread-permissions-types.js';
 import { threadPermissions } from '../types/thread-permission-types.js';
-import { threadTypeIsThick } from '../types/thread-types-enum.js';
 import { useDispatchActionPromise } from '../utils/redux-promise-utils.js';
 import { useSelector } from '../utils/redux-utils.js';
 
@@ -98,7 +97,8 @@
 
   if (
     !targetMessageInfo ||
-    (!targetMessageInfo.id && !threadTypeIsThick(threadInfo.type)) ||
+    (!targetMessageInfo.id &&
+      !threadSpecs[threadInfo.type].protocol.canActionsTargetPendingMessages) ||
     (threadInfo.sourceMessageID &&
       threadInfo.sourceMessageID === targetMessageInfo.id)
   ) {
diff --git a/lib/shared/sidebar-utils.js b/lib/shared/sidebar-utils.js
--- a/lib/shared/sidebar-utils.js
+++ b/lib/shared/sidebar-utils.js
@@ -12,7 +12,7 @@
   useThreadHasPermission,
   userIsMember,
 } from './thread-utils.js';
-import { threadTypeIsPersonal } from './threads/thread-specs.js';
+import { threadSpecs, threadTypeIsPersonal } from './threads/thread-specs.js';
 import type { ChatMessageInfoItem } from '../selectors/chat-selectors.js';
 import { chatMessageItemEngagementTargetMessageInfo } from '../shared/chat-message-item-utils.js';
 import { messageTypes } from '../types/message-types-enum.js';
@@ -214,7 +214,8 @@
 
   if (
     !messageInfo ||
-    (!messageInfo.id && !threadTypeIsThick(threadInfo.type)) ||
+    (!messageInfo.id &&
+      !threadSpecs[threadInfo.type].protocol.canActionsTargetPendingMessages) ||
     (threadInfo.sourceMessageID &&
       threadInfo.sourceMessageID === messageInfo.id) ||
     isInvalidSidebarSource(messageInfo)
diff --git a/lib/shared/threads/protocols/dm-thread-protocol.js b/lib/shared/threads/protocols/dm-thread-protocol.js
--- a/lib/shared/threads/protocols/dm-thread-protocol.js
+++ b/lib/shared/threads/protocols/dm-thread-protocol.js
@@ -482,6 +482,8 @@
   },
 
   uploadMultimediaMetadataToKeyserver: false,
+
+  canActionsTargetPendingMessages: true,
 });
 
 export { dmThreadProtocol };
diff --git a/lib/shared/threads/protocols/keyserver-thread-protocol.js b/lib/shared/threads/protocols/keyserver-thread-protocol.js
--- a/lib/shared/threads/protocols/keyserver-thread-protocol.js
+++ b/lib/shared/threads/protocols/keyserver-thread-protocol.js
@@ -299,6 +299,8 @@
   },
 
   uploadMultimediaMetadataToKeyserver: true,
+
+  canActionsTargetPendingMessages: false,
 });
 
 function mediaIDIsKeyserverID(mediaID: string): boolean {
diff --git a/lib/shared/threads/thread-spec.js b/lib/shared/threads/thread-spec.js
--- a/lib/shared/threads/thread-spec.js
+++ b/lib/shared/threads/thread-spec.js
@@ -214,6 +214,7 @@
     +breadCrumbs: (ancestorPath: React.Node) => React.Node,
   },
   +uploadMultimediaMetadataToKeyserver: boolean,
+  +canActionsTargetPendingMessages: boolean,
 };
 
 export type ThreadSpec = {