I have noticed a weird issue with Windows, where alt-tabbing from and into the games breaks the way the games work. I have been observing inconsistencies in input latency, bad frame pacing etc., regardless of "Fullscreen optimizations" disabled or enabled, which I thought was the culprit. Every game run just fine only until alt-tabbing out to the desktop or other applications and when alt-tabbed back, they start to suffer with frame pacing issues like judder, altered input latency and Double buffering Vsync being overridden with Triple buffering, things like that. Every game might look like running in fullscreen but, seems like they are actually not, but worse. Pressing Alt-Enter a couple of times or toggling in-game settings to fullscreen fixes it and sometimes, restarting is the only way. The game has to start in fullscreen (from scratch) by itself to run with pure performance. If navigated to other applications by minimizing or alt-tabbing or whatever key combination, the game breaks its performance. For instance, Grand Theft Auto V uses Double buffering Vsync, maintaining steady frame pacing, input latency, with no interruptions in the middle of the game like navigating to other applications. Now, when alt-tabbed to any application/desktop and back into the game, the game might still look like it is running is normal fullscreen mode like before, but, the Vsync turns into Triple buffering mode and the frame pacing becomes terrible with input lag variation. Alt-Enter might fix the issue sometimes and sometimes not. Maybe this is how the "Desktop Window Manager" in Windows handles applications and has trouble turning games back to the state, where they were before multitasking to other applications, without having to restart the whole game or toggle screen modes in game settings. Maybe games run in "Flip Mode Presentation" which is the new way Windows handles games in Borderless Fullscreen mode and cannot be fixed unless the behavior is modified by the developers. I used a tool called "PresentMon" to monitor what is going on behind the scenes and the tool shows the latency being increased after alt-tabbing from the game and back into the game. You can refer to the picture, I attached. What do you think could be the cause for this problem? A nice explanation will be appreciated. Thank you.