Yeah same here. This discussion is needed. I need to see if the Streamlabs version is UWP or operating like a fullscreen borderless mode. I think Microsoft made some DirectX changes, but from my understanding now....these stutters are happening because of the desktop composite and the way the app uses the frame buffering. Developers do not want to remove code that still support Windows 7 and earlier. They can say what they want, but because this code is still present it causes stuttering to the DWM. It's called "Fullscreen Optimizations", which are implemented on the image. If you run your games in Windowed Fullscreen or Borderless Fullscreen, then you will notice that there is no stuttering. Microsoft apps or UWP apps run like this because that is how they should run. Fullscreen Exclusive is broken on purpose in Windows 10 so they can stop using Windows 7....thus it's coming to an end later this year. I'm not a theorist on it. If you ask a mechanic to change the oil in a car, then they will do it regardless of the car and not say, "you need to upgrade before I can change it." Now I know OBS is open source. If I knew C++ really well, then I would have helped in this area a long time ago. Microsoft is not slowing down gutting Windows 7/XP code to improve the frame buffering so apps can run a bit closer to kernel mode.I think it's time to bring this discussion back. I've installed Win 10 1903 update and games no longer stutters having playing videos on my second (60Hz) screen. Blizzard and discord clients with animated banners that were causing stutters in 1809 now working flawlesly.
OBS with preview mode is still causing issues! Ans this need to be investigated.
Monitor certification is the other problem. EDID's are F'd up in all places. Windows 10 correctly recognizes 59.94 and 60hz in the registry by applying the correct numerator and denominator, but the drivers may state 60hz and represent 59.94hz. I had to add additional EDID info, but we are supposed to be using the new EDID info by now.