HTML5 videos crashes Firefox

[Andrea Venturoli]

Hello.

Since a week or two my FireFox crashes as soon as an HTML5 video starts 
playing. This can be sistematically reproduced, for example, by opening 
YouTube and selecting a random video.

Notice I'm not that intrested in such videos, I just hate it when I open 
a page with one on it (possibly advertisement) and the 25 opened 
windows/tabs suddenly die.



Nothing is printed on the terminal apart from "Bus error (core dumped)".
Obviously the core file is useless, but I tried recompiling FireFox with 
debug symbols and that didn't make it any more readable (only some ?? in 
the stack trace).
"portupgrade -Rf firefox" was only a waste of time.
I switched from GTK2 to GTK3 (which I think became the default in the 
meanwhile), but the crashes weren't affected.
I deleted my config and rebuilt with default options, only to get the 
same behaviour.
I read disabling ALSA might solve, but it didn't (besides, it was 
enabled before the crashes started).
I remembered in the past we had to load sem.ko, but it didn't help either.



So I'm just looking for any hint that could help me get on the right 
track to debug this.
TIA to anyone who will answer.




Some info:
> % uname -a
> FreeBSD alamar.ventu 10.2-RELEASE-p14 FreeBSD 10.2-RELEASE-p14 #5 r297011: Fri Mar 18 10:48:43 CET 2016 root at alamar.ventu:/usr/obj/usr/src/sys/ALAMAR i386

> % ident /usr/ports/www/firefox/Makefile
> /usr/ports/www/firefox/Makefile:
> $FreeBSD: head/www/firefox/Makefile 411909 2016-03-25 23:30:06Z jbeich $



  bye
	av.