last night the wfgeoLink function hook was removed from the MapSources extension. Why you did this and why nobody told this to the community? On the German Wikivoyage #geolink is used for about 30.000 times.
This hook has nothing to do with the slippymap.
You did us a disservice.
By the way I am one of the former authors of this extension. But nobody made my a subscriber.