Topic on Extension talk:GitHub

Give me a Fatal Error after install:

[ca74c763] 2014-12-28 10:43:49: Fatal exception of type MWException

Solved removing with:

$ sudo php composer.phar remove jeroen-de-dauw/mediawiki-github

Basically you just removed the extension. This does not resolve the underlying bug but avoids your issue of an infunctional wiki because of the GitHub extension being installed.

$wgShowExceptionDetails set to "true" would provide more information on the issue for an issue report on the extension's GitHub page.