When Firefox crashes, it usually records information about what was happening at that moment. You can submit that data to Mozilla and share it with forum volunteers to see whether it points to the solution. Please check the support article "Firefox Crashes" (especially the last section) for steps to get those crash IDs, and then post some of the recent ones here.

(While your Word file might have most of the same information, the version on the crash-stats server links to similar reports and the bug system, which makes our research much easier.)

Thanks for your reply. I took a look - now it makes more sense. Some of the crashes look like they were resolved, the most recent seem to be caused by a specific .ax file. I'm posting a few here - one seems resolved, the others aren't. Resolved (I think, happened twice). This seemed to be caused by Oom small: https://crash-stats.mozilla.com/report/index/bp-d0d4395c-fba9-4e39-a25e-38eee2140805

This one doesn't even have anything like it reported: https://crash-stats.mozilla.com/report/index/bp-9770bbdf-1e1c-414b-8531-7f12e2140811

This is the one that happened today, I'm posting one of the two: https://crash-stats.mozilla.com/report/index/bp-7aac47ec-5660-4017-8ed7-5fbf82140811

There are PLENTY more. According to the crash page, it's been crashing pretty regularly (sometimes multiple times a day) for months, over a year. I find it hard to believe it's just bugs in FF - I'm wondering if I have some add-ons or underlying issue that's causing it.

BTW, I use MBAM (paid version) and Avast, and run root kit scans with Tdsskiller, so I don't think it's malware.

Thanks again for your help and time.

(1) "OOM Small" usually indicates that some function exceeded the amount of memory Firefox allocated for it, and Firefox wasn't able to grab more memory. In this case, the report indicates 90% of all system memory used, which could be why Firefox died.

Was Firefox getting very sluggish before it crashed? When that happens, I usually exit Firefox and start it back up again, but there might be other techniques to free memory. Some users are experimenting with the buttons on the about:memory page.

(2) This is a Flash crash. If you haven't already, try disabling the protected mode feature of the Flash plugin. This involves creating or editing a settings file. The following pages/posts provide different ways to do that:

• Adobe support article under the heading "Last Resort": Adobe Forums: How do I troubleshoot Flash Player's protected mode for Firefox?

• Manual steps: https://support.mozilla.org/questions/968190?page=5#answer-509209

• Batch file to automate the manual steps: https://support.mozilla.org/questions/982093#answer-518078

Flash needs to completely unload from memory (exiting and starting Firefox up again might help) before this takes effect.

(3) I haven't seen this crash before, but then again, I certainly can't read every report. It seems that shortly after load Firefox is trying to demux an MPEG media file. Perhaps reloading a tab from a previous crash? I don't know whether there is a good workaround for this since it is an external component of Windows (or other codec suppliers).

Thanks for your help, and your quick replies. I'm not home right now, but will look at both the memory allocation and the flash suggestions. Perhaps that had been the issue all along. I'll mark this as solved and, if it continues, I'll open up another thread.

You can also try to disable hardware acceleration in Firefox if it is still enabled.

• Tools > Options > Advanced > General > Browsing: "Use hardware acceleration when available"

You need close and restart Firefox after toggling this setting.

• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes
• https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration

Some users have reported issues with avast! Try to disable it for a time.