Thread:Manual talk:Skin autodiscovery/Upgrading to 1.23/reply

I don't think this is a very good idea, especially for inexperienced users since 1.23 still looks for the skins in /skins if nothing else is specified in LocalSettings.php. and of one of the affected skins is used, especially as default skin. On my local installation deletion (or renaming) of the skins folder and or the Vector.php etc files caused a fatal error and Skin not found warnings.

Not sure why it worked for you, though. I guess you are using a custom skin or one that is already compatible?

The bundled skins will work and it's not that hard to migrate customs skins.