Exactly what the title says. If I turn on VSync on my 144hz monitor it’ll work fine. If I alt+tab to my other monitor while I’m in a game, it’ll drop down to 60 fps while it’s not the active window, but return to 144 fps when I go back to it. Now if I do this while the game is loading, i.e. joining a match, then it’ll be stuck on 60 fps. If I toggle VSync off and on again, still at 60 fps. If I turn VSync off, 300 fps. If I restart the game, still 60 fps with VSync on. I have checked all the settings, they’re still right. I have to restart my computer to get the 144hz VSync to work again.
Edit to add specs:
Windows 10 Home x64
Acer 24" 1080p 144hz
Dell 24" 1080p 60hz
MSI GTX 1060 OC 3GB
Ryzen 5 1600X 3.9 GHz
ASUS ROG STRIX B350-F GAMING
G.SKILL TridentZ RGB DDR4 3000 16GB
Kingston HyperX 120GB SSD