Have choice of mapsource in map tab

[LaurentG]

Currently, by default, displayed map is from Google Maps

I have found in the forum the undocumented feature to add "gpsProvider=osm" in [%General] section of xnview.ini file allow to switch.... not to OpenStreetMap, but rather to ThunderForest maps, with two major drawbacks
- display of the API Key Required message
- Maps a lot less detailed than the standard maps of OpenStreetMap.org

It would be great in a first step to switch from Thunderforest rendition to "real" OpenStreetMap.org

And mainly, in a second step, to allow user to choose whichever map source he wants, having only to provide the URL to get the different map tiles.

[Fotograf4848]

I'd also like to see this. The Google map lacks in details and contrast. OSM or OpenTopoMap would be really nice.