This is consistent on the latest versions of Chrome and Firefox.
PS - In spite of the rendering issue, it would be nice to be able to just paste in the GPS coordinates rather than dragging the marker to the location on the map.
From my experience it is internet issue not downloading the tiles. I also agree with Eric above the ability to paste in the co-ordinates would be far easier and more accurate than moving the pin, esp as I have to take the gateway with me to various locations for various reasons.
I just had the same ‘issue’. Map zoomed to 0,0 set to current location didn’t do anything though.
Zooming out, and manually moving the pin worked.
Problem solved
I faced the same problem.
Using current location was blocked in browser (chrome). I allowed it to use my current location and map was rendered successfully.
It seems that there is a bug within js code that avoids map to be configured correctly while the permission is not given.