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Lost Sync Data After Downgrading Firefox

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I updated Firefox in hopes of fixing an extension issue, it didn't, and the latest build leaks a lot of memory, i downgraded back, but then my profile couldn't load cuz it was an old version... Is there a way to get my sync data back and remain in the downgraded version? i tried copying the files inside my profile to the new one but it triggers the "create new profile for this installation" or "exit" pop up when launching...

I updated Firefox in hopes of fixing an extension issue, it didn't, and the latest build leaks a lot of memory, i downgraded back, but then my profile couldn't load cuz it was an old version... Is there a way to get my sync data back and remain in the downgraded version? i tried copying the files inside my profile to the new one but it triggers the "create new profile for this installation" or "exit" pop up when launching...
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cor-el said

Do you know which extension caused this issue? You can check the Firefox Task Manager (about:performance) and about:memory pages. Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is causing the problem.
  • switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
  • do NOT click the "Refresh Firefox" button on the Safe Mode start window

I don't think the extension was the issue honestly... It simply wouldn't download and give error, so i decided to update the browser to see if it would fix, the extension was Premid btw..

Also, sorry for the late reply but i didn't manage and ended up giving up... i'll keep on the latest version of FF.. for some reason none of my profiles worked so i started a new one, i remember my extensions tho i completely lost my session of 30+ tabs.. i'll be more careful next time, at least now i know FF doesn't take lightly to downgrades

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All Replies (6)

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Dinushi Dhananjani said

https://support.mozilla.org/en-US/kb/recover-user-data-missing-after-firefox-update

Hello, i've already try that, with the profile that has my data on it, if i click "Launch profile in new browser", it won't and instead show the "create new profile for this installation of firefox" or "exit" warning

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On the desktop you should see a folder called 'Old Firefox Data' open it and copy all the data by highlighting and selecting everything in that folder, then right click and select copy. Now open FIrefox. Head on over to about:profiles by typing it in your URL bar.

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Senali Madawala said

On the desktop you should see a folder called 'Old Firefox Data' open it and copy all the data by highlighting and selecting everything in that folder, then right click and select copy. Now open FIrefox. Head on over to about:profiles by typing it in your URL bar.

i'm sorry i can't find that folder could you tell me the exact path?

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Do you know which extension caused this issue?

You can check the Firefox Task Manager (about:performance) and about:memory pages.

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is causing the problem.

  • switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
  • do NOT click the "Refresh Firefox" button on the Safe Mode start window
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Chosen Solution

cor-el said

Do you know which extension caused this issue? You can check the Firefox Task Manager (about:performance) and about:memory pages. Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is causing the problem.
  • switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
  • do NOT click the "Refresh Firefox" button on the Safe Mode start window

I don't think the extension was the issue honestly... It simply wouldn't download and give error, so i decided to update the browser to see if it would fix, the extension was Premid btw..

Also, sorry for the late reply but i didn't manage and ended up giving up... i'll keep on the latest version of FF.. for some reason none of my profiles worked so i started a new one, i remember my extensions tho i completely lost my session of 30+ tabs.. i'll be more careful next time, at least now i know FF doesn't take lightly to downgrades