I'm trying to update the Extension:MobileDetect to extension registration. However, one of the features of this extension is that it introduces a global function called mobiledetect() that returns true if we're on a mobile device, and false otherwise. This allows admins to customize what extensions/configs/skins get loaded in LocalSettings.php, depending on the kind of device.

The problem is that the current extension registration system seems to lack a way to define global variables or functions early enough so they can be used in LocalSettings.php.