diff --git a/ts/components/conversation/composition/CompositionBox.tsx b/ts/components/conversation/composition/CompositionBox.tsx
index 70f09a1fa..bc8a2182e 100644
--- a/ts/components/conversation/composition/CompositionBox.tsx
+++ b/ts/components/conversation/composition/CompositionBox.tsx
@@ -423,7 +423,7 @@ class CompositionBoxInner extends React.Component<Props, State> {
     const { isKickedFromGroup, left, isPrivate, isBlocked } = this.props.selectedConversation;
     const messagePlaceHolder = makeMessagePlaceHolderText();
     const { typingEnabled } = this.props;
-    const neverMatchingRegex = /($a)/;
+    const neverMatchingRegex = /(\W)$/;
 
     return (
       <MentionsInput