User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:31.0) Gecko/20100101 Firefox/31.0 (Beta/Release) Build ID: 20140715214327 Steps to reproduce: This bug was filed from the Socorro interface and is report bp-b0f9c0b8-b24f-4191-9e72-dc2e82140831. ============================================================= Firefox sometimes crashes when watching HTML5 videos on YouTube. This usually happens when I am seeking with the arrow keys.

This seems like a probable dupe of bug 1061025, there are a handful of such gstreamer->libav crashes: https://crash-stats.mozilla.com/query/?product=Firefox&version=ALL%3AALL&range_value=2&range_unit=weeks&date=10%2F18%2F2014+05%3A00%3A00&query_search=signature&query_type=contains&query=libavcodec.so&reason=&release_channels=&build_id=&process_type=any&hang_type=any

I first started getting these crashes with Firefox 30, and I am still getting them on Firefox 33.

I haven't seen these crashes on my machine since I think Firefox 35, so resolving this for now.

Reopening because I had a crash with this signature on Firefox 40.0. This may only affect Ubuntu builds and may be related to bug 1112371. Here is the crash report bp-b0f9c0b8-b24f-4191-9e72-dc2e82140831.

which ubuntu are you using? Ubuntu uses LibAV rather than ffmpeg, and the version found in some ubuntu version is very buggy.

I am using Ubuntu 14.04.

In my previous comment I pasted the wrong crash report. Here is the new report bp-e7c425d1-e558-4bf2-acf9-f37e92150826.

oh, it's gstreamer and ffmpeg plugin via gstreamer. nothing much we can do then. What about you set media.fragmented-mp4.ffmpeg.enabled=true how does that work for you?

Mozilla/5.0 (X11; Linux x86_64; rv:42.0) Gecko/20100101 Firefox/42.0 Iceweasel/42.0 Debian 8 Jessie 64bit If package gstreamer1.0-libav is installed, firefox crash whenever the page contains a video. GDB output: Program received signal SIGSEGV, Segmentation fault. [Switching to Thread 0x7fffb9dff700 (LWP 6440)] 0x00007fffc1efabd4 in ?? () from /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstlibav.so Removed the package, everythings works correctly.

yet another gstreamer crash, not much we can do. Please try with Firefox Beta (43)

alternatively, install a newer libav libavcodec.so.54 is old and buggy

gstreamer is going in bug 1234092