Anytime I maximize a window on any monitor (Mac or external), the UI flickers and doesn't refresh what's on the screen. This is happening with Parallels 14 since my Mac was updated to Mojave. (I did just update to 14.1.0 (45387) with the same result) Below is a link to a video of what's happening https://drive.google.com/open?id=1HSKZR3tSiVDWZlQIJit3DHig8FCpafwB
Hi @MilesM2 , in the virtual machine's configuration go to "Hardware">"Graphics" and increase the graphics memory to "1GB" ,change the resolution to "Best for external display".Then click "Advanced Settings", change 3D acceleration to DirectX9 and disable vertical synchronization.
Thanks Kebha, I had 3d acceleration disabled but when I set that to Direct X9, I no longer have this issue (note, I left all other settings as I had them, 2gb of memory, scaled resolution vertical sync turned on)