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Sync deleted prefs.js

  • 3 replies
  • 6 have this problem
  • 8 views
  • Last reply by cor-el

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I set up firefox on a new computer and wanted to import and sync all settings using Sync. But apparently Sync decided the new profile to be the better one and now I have two virgin prefs.js (which is very unpleasant as it contained a lot of add-on settings).

Does Sync keep backups of silently overwritten files?

How can I force Sync to ask me before making stupid guesses about which data to purge?

I set up firefox on a new computer and wanted to import and sync all settings using Sync. But apparently Sync decided the new profile to be the better one and now I have two virgin prefs.js (which is very unpleasant as it contained a lot of add-on settings). Does Sync keep backups of silently overwritten files? How can I force Sync to ask me before making stupid guesses about which data to purge?

Modified by wfox

All Replies (3)

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Sync doesn't backup files, but only backups up some personal data stored in the profile folder.

In the case of preferences only preferences that are specified and displayed on the about:config page under services.sync.prefs.sync.* are stored on the sync server.
Pref settings from extensions aren't among the preferences that are saved, so they get lost by using sync.

If you still have access to the old computer then it is better and safer to copy the files to an USB thumb drive and place them in the Firefox Profile Folder directly.

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Thank you. That is interesting although confusing as I think Sync managed to synchronize Add-On settings in the past.

Anyhow, a behaviour of deleting all settings that are not synced seems quite ill-formed to me.

In the result I will probably use an external synchronisation solution to keep my profile folders in sync. The only downside is that all my Add-Ons will get installed on my mobile devices also.

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You're welcome

Future Firefox versions will be able to sync extensions.