just found a fix for Resolution and Fullscreen problems...

[CalicoJack]

Select the Library tab present at top of the Steam client.
Right click on the game and select Properties from the list of options available.
Navigate to the General tab and here will see a Set Launch Options button.

add

-window-mode exclusive

in the Launch Options


Done!
now you have Exclusive Fullscreen mode.
i think this should work with every UnityEngine game that does not have a correct Fullscreen mode.




extra:
You may need to enable “Override High DPI scaling behavior” for the game .exe file.
It`s located in the game installation folder.

Right click on the game .exe and click “Properties.”
Go over to the Compatibility tab, enable “Override High DPI scaling behavior” and set the
Scaling Behavior to “Application.”





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