Requests for comment/Debugging at production server

Background
Debugging toolbar feature was introduced in MediaWiki 1.19.

Problem
Sometimes we have to debug on production wiki, but don't want to show internal information to normal users.

But the current architecture of debugging toolbar is available for everyone, so some internal information, like the server's directory structure, debug logs, and so on, can be leaked.

Proposal
Make only selected user can use debugging toolbar. Current implementation is using user rights (usedebugtoolbar, see ).