[Feature Request] Borderless fullscreen mode

[duke912]

add a borderless fullscreen option, so Lossless Scaling will work with the emulator

[Rosalie241]

I use Qt's fullscreen function, Qt has no borderless fullscreen function and I'm not adding platform specific code for this, maybe a thirdparty application like Borderless Gaming can help.

[duke912]

Yeah whatever, Borderless Gaming don't work