Thanks for the scene.
This is a critical bug in Online Maps, because of which, in Render to Texture mode the map was not positioned correctly when the texture size was not 512x512.
I am very surprised that no one wrote about this problem, because it can be seen visually that the tiles move (jump) when switching to another zoom level (for example, from 16.9 to 17.1).
This can be seen at 5 seconds of your video.
The problem has been fixed.
The new version will be available through the built-in update system in 24 hours.
P.S. Do not use the map in OnEnable, because it is a roulette - singletons of the map will be initialized or not yet.
Use Start method.
P.P.S. Your markers are located a bit higher than they should be.
Comment out the line (Layer_Manager.UpdateMarker):
screenPosition.y += markerRectTransform.rect.height / 2;
Infinity Code Team.
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