Hello,
Thank you for your patience.
We have done some more testing and on another machine we were able to reproduce the issue.
It seems like there is a problem with amount of frames that are being projected by CS:GO. In a Fullscreen windowed mode with an external display set as a primary one and on extend option. The game launched correctly but in-game experience was not satisfactory enough unless we lowered the amount of maximum FPS.
Firstly, we tried with highest possible and we did see the lags and stuttering BUT when we capped the FPS for 60 it was not present and the game played smoothly. We did try to increase the capped FPS and up to around 120 we did not see any changed. Around 200fps the game started to work really slowly.
This would also prove that other games can work normally as the ones you mentioned are capped for around 60fps.
What I would suggest for now is to lower and cap the FPS ratio in CS:GO as it seems to be an issue that the device is not able to project so many frames at once. If you would need a guide how to do it, here is the YT clip about it.
https://www.youtube.com/watch?v=PbTPNvbg228
Lastly, I would like to analyze the issue further. Could you please follow this link and gather log files for me?
https://support.displaylink.com/know...to-displaylink
I would like to see your exact setup and possible errors or information in the logs.