When I enter fullscreen mode the game moves to my secondary (60Hz) monitor and freezes my main (144Hz) monitor or turns the screen black. The mouse cursor remains on my main monitor, but when I move the cursor the effects are visible on the secondary monitor where the game is live. To be clear, the game is fully playable in fullscreen, but it's on the wrong monitor. I want to fullscreen the game on my main monitor to enjoy the 144Hz.
I've provided two photos: prntscrn.png is what print screen function captures and IMG_2687.jpg is what my monitors actually look like (left is secondary, right is primary)
Thank you for your report!
We're actually already tracking this issue in MC-150369, so I resolved and linked this ticket as a duplicate.
However, that ticket has already been resolved. Depending on the resolution, that can mean that it either will be fixed in the next version, or that it is not considered a bug and won't be fixed.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.