Firefox shouldn't crash. We probably can fix that. And the WebM issues, too. (But several users are reporting some unplayable Youtube videos in the past few days, and I'm not sure we've solved that one yet.)

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.

Meanwhile, as a quick test, could you test some of those problem sites in Firefox's Safe Mode? That's a standard diagnostic tool to deactivate extensions and some advanced features of Firefox. More info: Diagnose Firefox issues using Troubleshoot Mode.

You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" button > Restart with Add-ons Disabled
• Help menu > Restart with Add-ons Disabled

Not all add-ons are disabled: Flash and other plugins still run

After Firefox shuts down, a small dialog should appear. Click "Start in Safe Mode" (not Reset).

Any difference?

restarted firefox in safe mode, still won't work. Soundcloud won't work and webM give me a "Your video format or MME type is not supported. Closing mozilla in safe mode still gives me a crash reporter. This is very annoying switching between Mozilla and Chrome for things that aren't currently working in mozilla. some crash reports bp-87669e68-8dec-4828-881d-2f05a2140715 13/07/2014 2:22 AM 7dc05efe-faa1-4354-8f00-86ab1cdf9b71 12/07/2014 12:59 AM 8b811a70-a51d-4647-b5c8-1f4a933b4386 09/07/2014 10:51 PM 45d84997-3c8e-4de1-b93a-fb0d53fdb2f7 09/07/2014 1:14 AM c067a418-cbdc-4407-b07d-38aa3d70e192 07/07/2014 6:18 PM a0bfc8c3-52ad-4384-88a6-128dd84cca1a 04/07/2014 9:04 PM ff3b5aed-ce8e-442e-a6a6-4f8e9a079f08

Thank you for testing that, and for the crash IDs. It is hard for us to view the crash reports that do not start with bp. Could you click through those links to make sure the data got submitted, and then post the URLs direct to the crash stats site?

For WebM, does the problem occur with the test video on this site: http://www.webmfiles.org/demo-files/

If the problem only occurs on particular sites, could you post link to the problem pages?

By the way, the crash report that was "linkified" in your last post has many comments from users indicating that it occurred on shutdown. The crash itself relates to the media player, so perhaps if we can solve the media player problem, that will take care of the shutdown crashes, too.

If you are exiting Firefox when media is still playing, next time, please try stopping the media first to see whether that makes any difference.

the webm on the test site is just a rotating circle. I am not exiting when the media player is playing, but I think that might the problem as well. heres some: https://crash-stats.mozilla.com/report/index/3f3c14d5-0a46-4498-845d-2fab92140622 https://crash-stats.mozilla.com/report/index/a794eaab-cb30-4e4c-9fc1-e95a12140716 https://crash-stats.mozilla.com/report/index/2d234eb7-4d90-4b58-a567-a9dcd2140716

what i meant to say was I think the media player might be the problem , regardless of shutting down while it is playing or not. but a uninstall, reinstall has not fixed it

Two of those three were Flash hangs (the other one matched the one I viewed earlier).

Here are some standard recommendations for Flash problems:

(1) Disable hardware graphics acceleration in Flash

See this support article from Adobe: http://helpx.adobe.com/flash-player/kb/video-playback-issues.html#main_Solve_video_playback_issues

(2) Disable the protected mode feature

This involves creating or editing a settings file. You can disable that by 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.

There is a setting to disable WebM in Firefox. I would be surprised if that has been set, but it's worth a check.

(1) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

(2) In the search box that appears above the list, type or paste media and pause while the list is filtered

(3) Scroll down to the media.webm.enabled preference and if it is bold and user set to false, double-click it to restore the default value of true.

If you notice any other media. preferences customized, those would be worth a look at potentially affecting the player.

youtube videos play fine so im not sure about the last resort thing. I unchecked the disabled hardware acceleration thing and that didnt work. and media.webm. enabled is set to true.

Protected mode works on some systems and not others. Since two of your four crash reports were related to Flash, I thought it was worth a try, but it's up to you whether you want to try it.

I'm not sure whether the issue with WebM video is a setting issue or a program files issue or a system issue.

Create a new Firefox profile

A new profile will have your system-installed plugins (e.g., Flash) and extensions (e.g., security suite toolbars), but no themes, other extensions, or other customizations. It also should have completely fresh settings databases and a fresh cache folder.

Exit Firefox and start up in the Profile Manager using Start > search box (or Run):

firefox.exe -P

Don't delete anything here. Any time you want to switch profiles, exit Firefox and return to this dialog.

Click the Create Profile button, choose a name like TESTING, and skip the option to change the folder location. Then start Firefox in the new profile you created.

Any better results with WebM video or shutdown?

When returning to the Profile Manager, you might be tempted to use the Delete Profile button. But... it's a bit too easy to accidentally delete your "real" profile, so I recommend resisting the temptation. If you do want to clean up later, I suggest making a backup of all your profiles first in case something were to go wrong.

Clean Reinstall

A regular reinstall may leave some stray files in your programs folder. This method is a bit cleaner.

(1) If needed, download a fresh installer for Firefox 30 from https://www.mozilla.org/firefox/all/ to a convenient location. (Scroll down to your preferred language.)

(2) Exit out of Firefox.

(3) Rename the folder

C:\Program Files (x86)\Mozilla Firefox

to

C:\Program Files (x86)\OldFirefox

(4) Run the installer you downloaded in #1. It should automatically connect to your existing settings.

Does Firefox behave more normally?

Note: Some plugins may exist only in that OldFirefox folder. If something essential is missing, look in these folders:

• C:\Program Files (x86)\OldFirefox\Plugins
• C:\Program Files (x86)\OldFirefox\browser\plugins

tried both and they didnt work. I renamed mozilla to oldfirefox and ran the re installation thing from the download.

https://crash-stats.mozilla.com/report/index/a794eaab-cb30-4e4c-9fc1-e95a12140716 https://crash-stats.mozilla.com/report/index/2d234eb7-4d90-4b58-a567-a9dcd2140716 two more reports

Both of those crash reports indicate a hang in the Flash plugin. Did these cause a complete Firefox crash? Hopefully not, but they could explain why the Flash player isn't playing. Would you reconsider disabling the protected mode feature to see whether that helps?

tried disabling the protected mode and it didnt help

Hi HeartBreaker1, it didn't help with Flash crashes, or didn't help with WebM not playing or crashes at shutdown?

Regarding the videos that give the error message about an incorrect MIME type (typo: MME), this could be a problem on the site. Example: Trying to access live video at http://www.bloomberg.com/tv/ and keep getting message "No video with supported format and MME type found".

However, I'm puzzled that you couldn't play the video on the demo site either (icon circling but no error message). In that case, is it possible that Adblock was coming into play? If you checked it in Safe Mode or the TEST profile, then Adblock would not be a factor.

For SoundCloud, is there a page that demonstrates the problem that you could post a link to?

You may be missing a codec to play this content or support for specific MIME types if you get such a error message unless there is a problem on the website.

• https://developer.mozilla.org/Media_formats_supported_by_the_audio_and_video_elements
• https://developer.mozilla.org/Properly_Configuring_Server_MIME_Types
• https://developer.mozilla.org/How_Mozilla_determines_MIME_Types

man this is so frustrating. For soundcloud i just click the play button but nothing happens.

I tried without adblock and that still doesnt work

Did Soundcloud ever work on Firefox? I wonder whether some media components might be missing. There is a media feature pack for European versions of Windows 7. I don't know whether that is appropriate for your Windows, but you could take a look:

• Media Feature Pack for Windows 7 N with Service Pack 1 and Windows 7 KN with Service Pack 1 (KB968211)
  http://www.microsoft.com/en-us/download/details.aspx?id=16546

yeah it used to work, everything used to work