Context path changes causes @mention avatar thumbnail to not display

Summary

If the context path is updated, the avatar thumbnail image does not display when using an @mention. Testing revealed that this applied to any user whose profile picture was created before the context path change. Problem does not occur for user profile pictures uploaded after the context path change.

Environment

Confluence version 6.4.1
Not dependent on OS, DB or browser

Steps to Reproduce

1. Create a user profile and add a avatar picture.
2. Stop Confluence.
3. Change the context path value within the server.xml and confluence.cfg.xml files.
4. Start Confluence
5. Create a page and add an @mention.

Expected Results

The user should be found and their avatar thumbnail image should appear when being @mentioned.

Actual Results

While the user should be found, no avatar thumbnail image displays when being @mentioned.

Workaround

1. Locate every record in the content table with a title of 'user-avatar' created prior to the change in context path:

   select * from content where title = 'user-avatar' and creationdate > timestamp '2017-11-05 00:00:00';
   

2. For every record returned, delete the corresponding records in the contentproperties table based on contentid.
3. Likewise, delete the corresponding records in the imagedetails table based on contentid from content table equalling the attachmentid in imagedetails table.
4. If there are entries in the content table with a value in the prevver column, delete these records.
5. Delete every 'user-avatar' record from the content table.
6. In Confluence, rebuild the Content Index.
7. For each user included in the delete statements above, readd their profile picture.
8. When you do a subsequent @mention, you will need to type in a minimum of 3 characters before the profile thumbnail appears.

While this works, this will not be practical for larger user populations.