JIRA does not escape special character from username when opening JQLs from Delete User dialog

Summary

When deleting a user, if the user has involved in some issues as assignee and/or reporter, JIRA will display JQL links to those issues. If the username contains a special character, the links do not escape the special character and consequently throw JQL format errors.

Steps to reproduce

1. Create a user with this username: fake@localhost (@ is a special character in this case, which is common where username is the same as email address)
2. Set the user as reporter of 1 issue and assignee of another
3. Go to User Management -> Users -> attempt to Delete fake@localhost
4. Confirm that JIRA display 2 JQL links as follows:
   
5. Click the links

Expected behavior

The JQLs work correctly and display the corresponding issues

Actual behavior

JIRA fails to escape the special character and throws a warning:

Workaround

Manually wrap the username inside double quotes and perform the search again e.g.:

reporter in ("fake@localhost") ORDER BY priority ASC