Overlay programs like RTSS causing UI elements to flicker

Since around patch 8.1 there is a pretty annoying bug that randomly cause parts of the UI to flicker (like parts of the map, icons, bars). From my personal testing i noticed that its caused by RivaTunerStatisticServer (RTSS) which im using to track my CPU/GPU usage/temps and display them on the screen like this: https ://i.imgur.com/2we7sBR.jpg

So far i noticed that this is happening only in DX12 and when the overlay is enabled. Turning it off stops the flickering.

At this point i tried pretty much everything - fresh windows, different drivers reinstalled with DDU, no addons, fresh game installation and even a new GPU.

A few examples here:
https ://i.imgur.com/a7XSUk1.mp4 flickering Icons

https ://i.imgur.com/hyrLoKb.mp4 flickering parts of the map

https ://i.imgur.com/NuL8uec.mp4 same issue

After playing on the SL beta i noticed that its happening there too. WoW Classic is not affected by this.

Hey, Adlian! Overlays are not officially supported to work with our games and we often advise to disable or uninstall them temporarily as a general troubleshooting step. If compatibility with an overlay is a concern, the #support:bug-report forums would be a better place to report this issue so our compatibility team and quality assurance teams can look into this further.