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Is there an upper limit on number of bookmarks that can handle Firefox Sync?

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OS: Ubuntu 16.04.5 64-bit (on both devices)

Two devices use the same Firefox Sync account to sync bookmarks.

I have hard time to sync them. Currently I have 3784 entries in bookmarks collection; one of devices fails to get them in sync. I have to use "Restore from backup" instead, which is a lame workaround.

Is there a documented upper limit of bookmarks (and/or other hard limits that apply) that Firefox Sync can actually handle?

OS: Ubuntu 16.04.5 64-bit (on both devices) Two devices use the same Firefox Sync account to sync bookmarks. I have hard time to sync them. Currently I have 3784 entries in bookmarks collection; one of devices fails to get them in sync. I have to use "Restore from backup" instead, which is a lame workaround. Is there a documented upper limit of bookmarks (and/or other hard limits that apply) that Firefox Sync can actually handle?

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There is only a limit for the payload used for synced tabs and a date/time range for the history. I don't think there is a limit for the bookmarks, but bookmarks are synced in chunks of a few hundred items (200), so it takes some time to sync a large amount of bookmarks.

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

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

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

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

You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.

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Thanks for the comment.

The latest entry from about:sync-log (error log)

https://pastebin.com/vqUk3SGQ

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There seem to be errors with the bookmarks and you also seem to quite a few of them as I see a mention of over 3000 blocks. If I look at the log then I see a lot of lines about reparenting blocks.


If you use Sync then best is to disconnect Sync temporarily during troubleshooting.

You can check for problems with the places.sqlite database (bookmarks and history) in the Firefox profile folder.

  • use "Verify Integrity" button on the "Help -> Troubleshooting Information" (about:support) page
    in case errors are reported close and restart Firefox and retry

See also:

If "Verify Integrity" button on the "Help -> Troubleshooting Information" (about:support) page cannot repair places.sqlite then remove all places.sqlite files in the Firefox profile folder. Firefox will rebuild places.sqlite and restore the bookmarks from a recent JSON backup in the bookmarkbackups folder.

You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.