Resolution change and fps drops "fix": What I've found that worked for me

[OV3RH34T]

I don't know if this was already posted but here it goes:

The "fullscreen" option given in the settings is actually a borderless fullscreen, which causes a lot of performance problems and instability.
It also prevents resolution change as the game will always run in the native screen resolution. Even if you lower the screen resolution so that the game runs in a lower resolution, it will still be borderless fullscreen and you will still have bad FPS drops.

Solution: Change the game to windowed mode and change to the desired resolution. Then Press Alt + Tab at the same time while ingame to try and get the game to "real" fullscreen. It might not work a few times since Alt is reserved for using the interface, you have to try a few times, at the exact same time. This will allow you to change the resolution properly in the settings now that it is in proper fullscreen it will also reduce the FPS's drops because borderless puts alot more strain on your pc.

This is what worked for me, it might not work for you, since it depends alot on your setup.
What might also help is giving higher priority to bns in the task manager, but for me the charm was really Alt + Enter,

PS: My native resolution is 1950*1080 and somehow when I try to "real" fullscreen with that res, the image doesn't fit the whole screen, leaves 2 black bars on the sides as if it was playing a ratio different from 16:9. Dunno why. All the other resolutions seem to work fine tho. Playing fullscreen now in a lower res with 60 constant FPS's even with 10 people on screen spamming skills. FPS drops are also reducing even comparing the borderless fullscreen vs the real fullscreen on my native res.