Fullscreen stretches to both monitors with Forge

[Pojkil]

I have dual monitor setup - with  vanilla fullscreen stretches to focused monitor (wanted behavior)

But with Forge fullscreen stretches to both monitors

 

Dont think its setup problem because vanilla works fine

Anybody knows fix?

 

Arch Linux - tried both clean Latest and Recommended

If more info needed - write

[LexManos]

As far as I know, we do not touch anything that would cause this. We dont touch how minecraft creates the intial display or what monitor it locks to.

You may need to see your graphics settings to see if you can specify an affinity for the fullscreen to use.

But i'll poke fry about this, he's our rendering guy. Sadly tho, hes out of country {as am I} so don't know how fast he'll be able to get back to you.