Manual:$wgResourceLoaderDebug

ResourceLoader: $wgResourceLoaderDebug
The default debug mode (on/off) for ResourceLoader requests.
Introduced in version:1.17.0 (r73568)
Removed in version:still in use
Allowed values:(boolean)
Default value:false

Details edit

The default debug mode (on/off) for ResourceLoader requests. See also ResourceLoader/Features#Debug mode for more about what the debug mode does.

You can achieve a similar result by setting the resourceLoaderDebug cookie (or, for a single request, the debug URL query parameter).

See also edit