Bug 256802

Good afternoon, When using WebKitGTK+-2.40.1 on an Intel Iris GPU (both from a Skylake and a Coffee Lake CPU), applications which use WebKit (MiniBrowser and Epiphany at least) have constant flickers which make the window entirely unusable. It doesn't seem to be reproducible on a 11th-gen Intel CPU, but on a Skylake (6th gen) and a Coffee Lake (8th gen) CPU, it's easily reproducible by opening a window and going to webkit://gpu, webkitgtk.org, or google.com. For what it's worth, Haswell CPUs and their internal GPUs are unaffected, and NVIDIA/AMD GPUs don't seem to be affected either. There doesn't seem to be any useful console output unfortunately. Distribution is Linux From Scratch's development version, though it is reproducible on Linux From Scratch 11.3 as well. I'm one of the developers and I'm using a Skylake GPU for testing (HD 530). One of my users who is able to reliably reproduce this uses UHD 630 for a GPU. This only seems to occur on GTK-4, using a GTK-3 build of MiniBrowser has no problems. Current versions of applications in use: - Kernel 6.2.11 - Mesa-23.0.2 - Cairo-1.17.6 (tried 1.17.8 as well, no difference) - gstreamer-1.22.2 - Xorg-Server-21.1.8 - glibc-2.37 - gtk-4.10.3 It seems to show up regardless of desktop environment as well. I've tried downgrading GTK-4 all the way back to 4.8.3 and Mesa to 22.3.5 and it had no difference. Also attempted was downgrading intel-media-driver. However, using WebKitGTK-2.41.3 shows no problems at all, so I don't think this is a problem with the current development version. I'm not sure how to tell exactly when it was fixed though. I can downgrade to 2.40.1 and try getting a video if desired.