Hi Tom,
the actual button is default and built-in to the openlayers map script library loaded over CDN, so this is not something I can change really, this would be very complicated to do, most likely either use a local copy and edit the map script (which i dont want to do because it is thousands of lines written by many people as an open-source project and would also make it impossible to update the script) or use some plugin, which is also problematic, because I cant find anything like that.
However given this is used on many webpages in exactly the same way, it is likely people will understand. The actual button is part of the script that handles the actual loading of the map tiles etc., just like the Google Maps library.