I have recently asked for help here concerning several driver problems. One was that morphological filtering was not working in DX 10-11 games, other was that the radeon overlay was sometimes crashing the radeon host application. Another problem was that the performance metrics was not showing gpu vram usage.
I finally found the solution to all three of those problems. Turns out that such problems are caused by the latest "feature" added to Windows 10 by Microsoft in the Creator's Update called "Full Screen Optimizations". What this does is, even when a game is set to work in full screen mode, this feature turns it into a slightly modified form of borderless fullscreen. Because of this, morphological filtering does not work, vram usage can not be read and the overlay doesn't work as they all require full screen applications.
In order to turn off full screen optimizations, go to the application's .exe file, right click it, go to properties, compatibility and tick the box that says "disable full screen optimizations". This should fix your issues. I thought that AMD and all users should know that so I am posting this here. I hope this helps.
Thank you for this very useful feedback, it is much appreciated.
The last paragraph did resolve the flickering with mouse movement in the cockpit I was having with P3Dv18.104.22.16868 which was also the exact same symptoms the following video was showing (not my video).