How to get psychedelic video and crash: chmod

[tlaronde%kergis.com@localhost]

I was testing i915 (i965) and radeon Xorg configurations, and rendering
a simple mp4 video wouldn't work, either with xine(1) or vlc(1).

I suspected ffmpeg4; then libvdpau and then something else, and so on
and so on, until vlc messages gave me the hint: the permissions on
/dev/dri/card0 were not correct---and I don't know what program
changed the permissions; but the culprit probably is Xorg(1) when
testing configurations.

If you want to have a psychedelic rendering of whatever video, just,
as root, chmod 640 /dev/dri/cardX (the number you are using).

As a bonus, vlc (for example) will crash when you try to close it.

Side note: xine(1) doesn't work anymore for me; only vlc manage to
play the mp4 files (xine gives the sound, but with a black screen). I
gave up trying to figure out what was wrong.

And after all these tries, the only way to have a map as a background
(in news articles about the numerous wars going on---just pick up the
earth zone you're interested in: there is probably a war going on
near, and you will have maps) with firefox (117) was to disable
hardware acceleration.

Without this, firefox (I always run it from a dedicated xterm in
order to see the messages) will spit out endlessly error messages and
telling to "file bug"---from a web search, Linux users are in no
better position regarding this and hardware acceleration doesn't work
for them either.
-- 
        Thierry Laronde <tlaronde +AT+ kergis +dot+ com>
                     http://www.kergis.com/
                    http://kertex.kergis.com/
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