Solved firefox tab crash: /dev/dri/card0: Permission denied

While running firefox-88.0.1 on 6.9-mostly-current I was getting gmail
tab crashing with this on stdout:

libGL error: MESA-LOADER: failed to retrieve device information
libGL error: Version 4 or later of flush extension not found
libGL error: failed to load driver: i915
libGL error: failed to open /dev/dri/card0: Permission denied
libGL error: failed to load driver: iris

Surprisingly, despite my /etc/fbtab having

/dev/ttyC0 0600 /dev/console:/dev/wskbd:/dev/wskbd0:/dev/wsmouse:/dev/wsmouse0:/dev/ttyCcfg:/dev/ttyC4:/dev/drm0:/dev/drmR128:/dev/dri/card0:/dev/dri/renderD128

The /dev/dri/card0 device was owned by root. I couldn't reproduce the
conditions that led to this (I was switching consoles and poking at ddb
when I hit the problem)

The solution is to logout and log back to get the device owned by myself.

Thanks
Greg