OpenStreetMap not showing in geometry viewer

I've spent two days on this and still have no clue....

The openstreetmap basemap only worked once at the first try of pgadmin.

And it only worked for one database. 

I tried it on the second database it didn't work: no openstreetmap shown up.

I reinstalled it (macos), and it still didn't work for any database that I connected to.

I tried different browsers, cleared all browsers histories and cache.

I even tried to fire up pgadmin in a container, but the openstreetmap base map is still missing in the geometry viewer. 

where is osm, any idea? Thanks.