Hey there,
The developers are working on server browser improvements and fixes.
This issue has been reported more often, but thank you for noting what you have tried to fix it. This will help others understand the issue.
This issue is one I’ve personally not heard of much. Could you try switching between playing windowed and fullscreen while in the server browser and in between sessions?
See also: Upcoming features on the wiki for more information.
Be sure to read the [PC] Conan Exiles Bug Report Guidelines. Guidelines can be found 
pinned at the top of the related (sub)forum.
I have moved this thread to the PC bugs subforum, as it provides an issue report. I’ve also changed the title of this thread to make it more descriptive. Your thread will be seen regardless.