libva >= 2.17 is required for Xwayland support #132
Description
Because for years libva only supported DRI2, and Xwayland still only supports DRI3. Only in libva 2.17 was DRI3 support added to bridge the gap.
Without libva 2.17 you can still use X11 on native Xorg and native Wayland on Wayland compositors. Just not X11 on a Wayland compositor (which is unfortunately the default mode for Firefox).