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Experiencing slowness and frequent crashes

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  • 1 has this problem
  • 7 views
  • Last reply by drobertc

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[Child 5526, MediaDecoderStateMachine #3] WARNING: Decoder=7f41ba3ef400 Decode error: NS_ERROR_DOM_MEDIA_FATAL_ERR (0x806e0005) - RefPtr<MediaSourceTrackDemuxer::SamplesPromise> mozilla::MediaSourceTrackDemuxer::DoGetSamples(int32_t): manager is detached.: file /PROJECT/firefox-84.0+linuxmint1+tricia/dom/media/MediaDecoderStateMachine.cpp:3471


I get quite a few errors like these when I use Firefox, and I couldn't find anything about them on the web. If anyone knows what this means and if it can be fixed by me, or if it is a developer issue, please let me know.

[Child 5526, MediaDecoderStateMachine #3] WARNING: Decoder=7f41ba3ef400 Decode error: NS_ERROR_DOM_MEDIA_FATAL_ERR (0x806e0005) - RefPtr<MediaSourceTrackDemuxer::SamplesPromise> mozilla::MediaSourceTrackDemuxer::DoGetSamples(int32_t): manager is detached.: file /PROJECT/firefox-84.0+linuxmint1+tricia/dom/media/MediaDecoderStateMachine.cpp:3471 I get quite a few errors like these when I use Firefox, and I couldn't find anything about them on the web. If anyone knows what this means and if it can be fixed by me, or if it is a developer issue, please let me know.

All Replies (2)

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When are you getting these errors? Starting Firefox? Surfing? watching a clip? . . . .


Let’s do a full clean re-install;

Note: Firefox comes in three or more folders on all computers. They are;

Maintenance: (Programs Folder) <Windows Only> Firefox itself: (Programs Folder) And two folders in the profile of each user on the computer for each Firefox profile for that user.

If you remove the Firefox folder, the user profiles would not be affected.


Download Firefox For All languages And Systems {web link}

Firefox ESR; Extended Support Release {web link}

Beta, Developer, Nightly versions https://www.mozilla.org/en-US/firefox/channel/desktop/

Install Older Version Of Firefox {web link}


Save the file. Then Close Firefox.

Using your file browser, open the Programs Folder on your computer.

Windows: C:\Program Files C:\Program Files (x86) Note: Check Both Folders

Mac: Open the "Applications" folder. https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac

Linux: Check your user manual. If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it. See Install Firefox on Linux; https://support.mozilla.org/en-US/kb/install-firefox-linux

If you downloaded and installed the binary package from the Firefox download page, simply remove the folder Firefox in your home directory. http://www.mozilla.org/firefox#desktop ++++++++++++++++++++++++++++ Look for, and remove any Mozilla or Firefox program folders. Do not remove the Mozilla Thunderbird folder if there is one.

Do Not remove any profile folders.

After rebooting the computer, run a registry scanner if you have one. Then run the installer. +++++++++++++++++++++++++++ If there is a problem, start your Computer in safe mode and try again.

How to Start all Computers in Safe Mode; {web link} Free Online Encyclopedia

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FredMcD said

When are you getting these errors? Starting Firefox? Surfing? watching a clip? . . . . Let’s do a full clean re-install; Note: Firefox comes in three or more folders on all computers. They are; Maintenance: (Programs Folder) <Windows Only> Firefox itself: (Programs Folder) And two folders in the profile of each user on the computer for each Firefox profile for that user. If you remove the Firefox folder, the user profiles would not be affected.

My Firefox acted strange lately, so I ran it from the command line to see if anything pops up (using linux), and this was the message it showed me when it started freezing (repeated many times, but for the sake of readability I just posted one, they all had the same text in it). The problem seems to happen every time I open up Facebook in it, but it also shows up at random, on other sites that I visit. Firefox freezes, show a yellow bar with "site not responding" in the GUI, and my processor sits at 100% usage the entire time. In some cases even the computer itself freezes (I use the time with seconds, and I see it freeze in the taskbar). I don't really know if my computer is freezing and taking Firefox with it or the other way around, however, I didn't find an explenation of this error anywhere on the web. I will do a clean reinstall of the program, but still, if it is an error I hope someone could be able to explain what is wrong. If not, I hope it goes away with the reinstall. Thatk you for your time, and pardon my lack of information in the first post.