diff --git a/src/components/middle/message/ActionMessage.tsx b/src/components/middle/message/ActionMessage.tsx
index 8bd5f0870..6f76cadbb 100644
--- a/src/components/middle/message/ActionMessage.tsx
+++ b/src/components/middle/message/ActionMessage.tsx
@@ -309,7 +309,7 @@ const ActionMessage = ({
       return;
     }
 
-    // Keep as is for now to avoid breaking appearance order
+    // Message appearance animation works only if this timeout is not cleared
     setTimeout(markShown, appearanceOrder * MESSAGE_APPEARANCE_DELAY);
   }, [appearanceOrder, noAppearanceAnimation]);
 
diff --git a/src/components/middle/message/Message.tsx b/src/components/middle/message/Message.tsx
index e021e5570..37f9c1f95 100644
--- a/src/components/middle/message/Message.tsx
+++ b/src/components/middle/message/Message.tsx
@@ -530,7 +530,7 @@ const Message = ({
       return;
     }
 
-    // Keep as is for now to avoid breaking appearance order
+    // Message appearance animation works only if this timeout is not cleared. Migrate to `sibling-index()` when baseline widely available.
     setTimeout(markShown, appearanceOrder * MESSAGE_APPEARANCE_DELAY);
   }, [appearanceOrder, noAppearanceAnimation]);
 
diff --git a/src/components/middle/message/SenderGroupContainer.tsx b/src/components/middle/message/SenderGroupContainer.tsx
index 89c82d733..0076e85d5 100644
--- a/src/components/middle/message/SenderGroupContainer.tsx
+++ b/src/components/middle/message/SenderGroupContainer.tsx
@@ -92,7 +92,7 @@ const SenderGroupContainer: FC<OwnProps & StateProps> = ({
       return;
     }
 
-    // Keep as is for now to avoid breaking appearance order
+    // Message appearance animation works only if this timeout is not cleared
     setTimeout(markShown, appearanceOrder * MESSAGE_APPEARANCE_DELAY);
   }, [appearanceOrder, noAppearanceAnimation]);