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Crash while syncing in Firefox 55 (Firefox is not responding)

  • 14 replies
  • 21 have this problem
  • 11 views
  • Last reply by SabreWolfy

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Hello.

Since Firefox 55 there is an issue with syncing using Mozilla Sync.

It still persists and leads to a frozen Firefox "not responding" in Windows.

Also with 55.0.3 - no matter if x86 or x64, this problems exists. The browser gets stuck within the sync process and has to be shut down using task manager. If you are lucky the next try of syncing will work correctly and then FF works fine.

This has never been an issue with 54.0.1 - I cross checked by reinstalling and testing FF 54.

This is approved in my environment with 3 different machines and 4 different Windows installations.

It even happens with no add-ons at all and checking the date of "last sync" you can easily see, that syncing didn't complete and this stalls Firefox and renders it useless.

If the syncing works, FF 55 also works as normal. Unfortunately, in this event NO error reports are generated. On none of the machines. Which means I cannot create a crash log of the problem.

I am not syncing everything, only history, password and bookmarks. No open tabs, add-ons or settings.

Is there a fix for this problem? Thanks in advance.

Hello. Since Firefox 55 there is an issue with syncing using Mozilla Sync. It still persists and leads to a frozen Firefox "not responding" in Windows. Also with 55.0.3 - no matter if x86 or x64, this problems exists. The browser gets stuck within the sync process and has to be shut down using task manager. If you are lucky the next try of syncing will work correctly and then FF works fine. This has never been an issue with 54.0.1 - I cross checked by reinstalling and testing FF 54. This is approved in my environment with 3 different machines and 4 different Windows installations. It even happens with no add-ons at all and checking the date of "last sync" you can easily see, that syncing didn't complete and this stalls Firefox and renders it useless. If the syncing works, FF 55 also works as normal. Unfortunately, in this event NO error reports are generated. On none of the machines. Which means I cannot create a crash log of the problem. I am not syncing everything, only history, password and bookmarks. No open tabs, add-ons or settings. Is there a fix for this problem? Thanks in advance.

Chosen solution

For me the problem seems to be solved with beta 8 of version 56.

Even the hard test of a notebook which wasn't powered up for 10 days (= many things to sync) was successful without crashing FF.

Hopefully the 56 release version will also work this way.

Read this answer in context 👍 2

All Replies (14)

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Have you tried a complete reinstall of the browser or resetting the settings to default and trying to sync then? Also, make sure you restarted your PC after the Update.

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I took a fresh Windows 7 installation with FF 55.0.3 x86. Installed, added no add-ons, acitvated sync. Leads to not responding every 2-3 start of FF.

Uninstalled. Installed x64. Same result.

This also applies for my existing installations. When I remove v55 and switch back to 54.0.1 this never happen. Sync always works w/o stalling Firefox. :-(

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Interesting, have you tried development versions, is the issue there?

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I will test Beta 56 on one of my installations.

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I can second cor-el's opinion. Corrupted Database can and will cause issues with syncing. Completely slipped my mind!

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Ok, I used the "Places Maintenance" on all machines which are syncing with this account.

Unfortunately the problem persists (on all machines). When the crash happens, the syncing takes much too long - even when only minor changes have to be synchronized.

When the crash doesn't happen, sync process is much quicker and Firefox is stbale as with version 54.0.1 as soon as as syncing finished successfully.

Will test Beta 56b8 now.

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Short tests with 56b8 (x64) look promising on two of the machines. Sync after opening FF very fast w/o the "not responding".

I'll keep on testing and will report back.

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Chosen Solution

For me the problem seems to be solved with beta 8 of version 56.

Even the hard test of a notebook which wasn't powered up for 10 days (= many things to sync) was successful without crashing FF.

Hopefully the 56 release version will also work this way.

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I have continued testing on 4 machines. Syncing works so fast with Beta 56 and no more crashes at all. Also Firefox itself is much smoother and memory usage has been reduced.

Beta 8 and now Beta 9 look really promising.

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Thanks for keeping us updated. Will suggest the same to people with similar issues, to try and go with the Beta versions. If you have any issues with them, keep us informed.

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News: Beta 8 und 9 of FF 56 worked flawlessly. No crashes while syncing.

Now, with Beta 10 installed today, another crash happened.

Someone else (who is on the Linux platform, not Windows) documented the problem which he experienced when syncing: https://bugzilla.mozilla.org/show_bug.cgi?id=1397163

When bookmarks are modified on one machine the syncing crashes on other computers using this sync account.

Either the sync wheel spins indefinitely or the complete browser crashes.

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You can open about:sync-log via the location bar to see if there are recent error logs available. You can upload a recent log if the log is too big to put in a reply.

You can toggle this pref temporarily to true to get a Sync log in case of success to test this.

  • services.sync.log.appender.file.logOnSuccess = true

Do not forget to reset services.sync.log.appender.file.logOnSuccess after you are done testing.

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