User Mention Dropdown Not Appearing in Hangout Reply Box

Title: User Mention Dropdown Not Appearing in Hangout Reply Box

Description:
While attempting to tag users in the reply box of a Hangout post, the user mention suggestion dropdown is not appearing. Normally, when typing “@” followed by a username or keyword, a list of matching users should be displayed for selection. However, in this case, no suggestions are shown, even after entering valid names or partial keywords.

Current Behavior:

• Typing “@” does not trigger the user suggestion dropdown.
• Entering a full or partial username still does not display any suggestions.
• If a valid username is manually typed in full and submitted, it correctly tags the user after posting.

Expected Behavior:

• Upon typing “@” followed by at least one character, a dropdown list of suggested users should appear.
• The list should dynamically update based on the entered keyword.

Steps to Reproduce:

1. Navigate to a Hangout post.
2. Click on the reply/comment box.
3. Type “@” followed by a username or keyword.
4. Observe that no suggestion dropdown appears.

Impact:

• Users may find it difficult to tag others unless they know the exact username.
• Reduces usability and efficiency in conversations.

Additional Notes:

• Tagging works only when the exact username is entered manually.
• The issue seems to be limited to the suggestion dropdown functionality.

Priority: Medium

Attachments: