My laptop has Intel/Nvidia hybrid graphics. I noticed windows (especially Files) under Gnome flicker a lot when resizing under hybrid mode. There’s no such issue when using Nvidia card only. I also have a PopOS partition which doesn’t have this problem even in hybrid mode.
Thank you! You give me the direction. I use the original Manjaro setup, so there is no content in configuration file for hybrid mode. But I created one with Option "TearFree" "true", and it fixed the problem.