Current implementation of oauth for WCQS (implemented by: https://phabricator.wikimedia.org/T251498) uses nginx for authorization and as such, doesn't add any gui elements related to being logged in. This may confuse users, because the fact that they are logged into commons.wikimedia.org isn't really obvious. This in turn may lead to security issues (leaving commons account logged in unintentionaly).
To the upper left corner to the WCQS GUI add:
- user name
- link to the logout page (https://commons.wikimedia.org/w/index.php?title=Special:UserLogout)