Issue Summary

It happens when the current user does not have [Browse Users] global permission.
In issue search, the selected users for assignee will be lost when shift from advanced mode to basic mode.

Steps to Reproduce

1. Remove [Browse Users] permission for a group
2. Login Jira with a user belong to the above group
3. Move to Issues > Search for issues
4. Click [Advanced] to go to advanced mode.
5. Input a JQL like below

   assignee in (other_user_name)
   

6. After search result returned, go back to basic mode
   

Expected Results

Assignee will have user selected.

Actual Results

Assignee loose the selection of  users.

Workaround

Currently there is no known workaround for this behavior.