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Firefox 29 is painfully slow

  • 8 replies
  • 470 have this problem
  • 7643 views
  • Last reply by Rich Kellogg

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What happened with Firefox 29? It is PAINFULLY slow. Sometimes switching between tabs takes a matter of seconds. Have a video running and FF often times out when switching between tabs and needs to be shut down.

Not running a slow or overloaded system by any means. Something is very wrong with this update.

Any idea how to fix this or degrade to FF 28, which worked amazingly well?

All Replies (8)

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Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance).

  • Do NOT click the Reset button on the Safe Mode start window.

It is possible that your security software (firewall, anti-virus) blocks or restricts Firefox or the plugin-container process without informing you, possibly after detecting changes (update) to the Firefox program.

Remove all rules for Firefox and the plugin-container from the permissions list in the firewall and let your firewall ask again for permission to get full, unrestricted, access to internet for Firefox and the plugin-container process and the updater process.

See:

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Had this problem too, here's what worked for me; open task manager, go to processes, right click on Firefox, choose set priority set it to high.

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This helped a little but not much.

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Mozilla's support for faulty products is it's always you, never them. Has to be an add-on or extension. If it's not that they blame your antivirus. If it's not that they blame your OS. If it's not that they'll say your specs need upgrading even when every other browser manufacturer works fine. Safari's a beast and that work faster than FF. I just started using Chrome more and more. Mozilla doesn't seem to care about users. I even stopped using Thunderbird since it's just as buggy.

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If the safe mode suggestion does not resolve your issue, please consider creating a new thread containing the specific details of your issue.

Also include troubleshooting information when asked.

Doing so will allow the Mozilla volunteers to give you solutions that are more helpful to you. This may help them to solve your problem faster and more efficiently.

Please, feel free to post the link to your thread on this thread for volunteers interested in assisting you.

Thank you.

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acsmith1972; If you are not going to post something useful, why post anything?

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alcahuete; When you tried Starting Firefox in Safe Mode, what did or didn't happen?

While you are in safe mode;
Firefox Options > Advanced > General.
Look for and turn off Use Hardware Acceleration.
Then check ALL of your settings. Browser and add-ons. Then restart.

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For me this problems started with version 29. In another thread it was suggested that hardware acceleration might be the problem. I turned off hardware acceleration, and that fixed the problem.

>>Tools>Options>Advanced>General Tab>Use hardware acceleration when available <<= uncheck