Redmine

This seems to be an issue with #15880, I seem to be having the same issue Rupesh J mentioned on 6-14. The problem appears to be the drop down menu is not always in the foreground, this seems to be the case with multiple themes, default included. I've attached a screenshot of the behavior while using the 'alternative' theme as it's the only one that visibly shows a hint of the misbehavior. With other themes the '+' appears to do nothing, but I assume the entire menu is behind the foreground.

Environment:
Redmine version 3.3.0.stable
Ruby version 2.2.5-p319 (2016-04-26) [x86_64-linux]
Rails version 4.2.6
Environment production
Database adapter Mysql2

Redmine plugins:
redmine_banner 0.1.1
redmine_checklists 3.1.3
redmine_ldap_sync 2.0.8.devel
redmine_local_avatars 0.2.0
redmine_logs 0.1.0
redmine_slack 0.1
redmine_theme_changer 0.2.0
sidebar_hide 0.0.7