How to enable native fullscreen on macOS ?

Hi, I play a French game called Dofus and I trie to optimize it for macOS.

The game was not retina compatible and can't switch to dark mode.

I fixed it by adding NSHighResolutionCapable key to true and NSRequiresAquaSystemAppearance to false in the info.plist file.

But as you see, the window isn't compatible with fullscreen mode. We have the + green button instead of the fullscreen button. I haven't access to source code, is there a key or another way to force it to adopt fullscreen mode ?

Thanks a lot

How to enable native fullscreen on macOS ?
 
 
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