Thread:Project:Support desk/Query On Logout Customization/reply

You shouldn't change the content of MediaWiki core files, for more information read this: Do not hack MediaWiki core

To change the contents of personal Urls, you can use the PersonUrls Hook, e.g. in an extension. And onmouseover and onmouseout aren't the best solutions for that, i think :) It's possible, that you create an own Extension, providing a ResourceLoader-module, which contains a javascript file. In this you can use jQuery to bind the mouseover and mouseout events to the logout link's jquery object, example:

That's much better as hacking core files, trust me :)