[Stable Update] 2022-08-07 - Kernels, Nvidia, Thunderbird, Cinnamon, Glibc, GCC, LibreOffice, Firefox, MangoHud, KDE-git

Same here: Firefox Coredump errors in journal
@anon89812132 posted about it HERE
Got rid of the Coredump errors by removing the libva-vdpau-driver.
Works for me as well.
At least a temporary workaround…