alexchandel
commented
6 years ago Note that in Unity 2018, the AV's Fullscreen menu item correctly resizes it to a new desktop, similar to what the green button should do, without changing the internal resolution. I can't fully recommend updating this project to 2018 though, because 2018 also deprecates MonoDevelop in favor of the bloated Visual Studio for Mac (300 MB vs 2.5 GB).
When AV's window is maximized using macOS's native fullscreen mechanism (clicking the green button, which moves the window to its own screen & expands it), Unity changes AV's screen resolution from whatever it was initially (e.g. a small value like 1280x800, for performance) to the maximum possible native resolution (e.g. 3360x2100). This can slow AV down by an order of magnitude, or make it unresponsive. This seems like some default Unity behavior.
It's also possible it happens because of the fullscreen expanding animation, and IIRC there's a way to opt out of the animation in Cocoa, but I can't remember the key.