I've recently updated to a fedora-30 + rpmfusion template for many of my AppVMs. I've begun to experience a lot of instability in the following situations:
* mpv playing video (often segfaults even before playback starts)
* vlc playing video (often segfaults before playback starts)
* Firefox rendering Google Maps -- I suspect this uses WebGL? (performance significantly degraded, occasionally the browser locks up)
* Firefox rendering video (occasionally the browser stops responding)
I double-checked my dom0 configuration against this page:
https://www.qubes-os.org/doc/intel-igfx-troubleshooting/
and in fact I even switched from the Xorg Intel driver to the modesetting driver (see https://github.com/QubesOS/qubes-issues/issues/4782) after I noticed from the Xorg log that there seemed to be some issues with my graphics card and the Intel driver. That didn't make much of a difference.
I've confirmed that it's something in the template: if I switch those AppVMs back to fedora-29 + rpmfusion, the problems go away. However I'm not really sure where to look from here to continue debugging. I'd appreciate any advice. Thank you.