You're a developer, and you need to debug a problem on a live Joomla! website. The Joomla! debug option in the Global Configuration helps, but you don't want the public to view the debugging code. How to debug without ruining the experience for normal users? allDebugControl to the rescue!
allDebugControl lets you control who gets to see the Joomla! debug code. By selecting a privileged user group or a specific user, allDebugControl makes Joomla! display the debug code only to those who need to view it.