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Sync not syncing preferences/settings between PCs.

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I have 2 computers that are both newly (and fully) formatted. Both are running win7 64bit with the latest firefox, and on the first one i have set up the entire Firefox with all the bookmarks and addons and settings.

When i log into sync on my 2nd computer it does sync the addons and the bookmarks - but none of the settings/preferences. I did make sure that the preferences are checked in the Sync settings, and i have tried the sync now button. I also tried logging out of sync and back into it, restarting my PC, resetting firefox to default and even deleting all firefox profiles and settings files. I have cookies allowed/enabled in case that is relevant, and firefox is updated to the latest version.

Can anyone tell me how do i make firefox sync the preferences? It is the most important part of the "sync" feature for me, and it is not working :(

I have 2 computers that are both newly (and fully) formatted. Both are running win7 64bit with the latest firefox, and on the first one i have set up the entire Firefox with all the bookmarks and addons and settings. When i log into sync on my 2nd computer it does sync the addons and the bookmarks - but none of the settings/preferences. I did make sure that the preferences are checked in the Sync settings, and i have tried the sync now button. I also tried logging out of sync and back into it, restarting my PC, resetting firefox to default and even deleting all firefox profiles and settings files. I have cookies allowed/enabled in case that is relevant, and firefox is updated to the latest version. Can anyone tell me how do i make firefox sync the preferences? It is the most important part of the "sync" feature for me, and it is not working :(

All Replies (20)

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Search in about:config for preferences that begin with this string. services.sync.prefs.sync.

Any with true as their value will synchronize, those that are false need to be toggled to true.

Overall, I find the synchronization of extension prefs very disappointing. With my mix of 21 extensions only a few sync'd prefs and those weren't the most complicated extensions I have installed.

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@the-edmeister Thank you for replying. I have tried what you suggested, but all of the strings were already set to True.

For testing purposes i tried making some new bookmarks and new settings on the 2nd computer, and then syncing on the first pc:

The new bookmarks synced normally, but none of the changed settings synced. I even recall having this issue earlier in 2015 (on different PCs and different accounts) but i did not make a support thread about it. Can anyone help please?

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Bump, help needed.

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bump. help needed.....

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Only prefs that have a corresponding services.sync.prefs.sync.* pref that is set to true will be synced to other devices. If you want to sync additional prefs then you can create a corresponding Boolean sync pref yourself and set the value to true.

  • services.sync.prefs.sync.*

There are services.sync.prefs prefs related to set which prefs to sync and you can set the corresponding services.sync.prefs.sync.xxx pref to false to prevent syncing a pref.

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cor-el said

Only prefs that have a corresponding services.sync.prefs.sync.* pref that is set to true will be synced to other devices. If you want to sync additional prefs then you can create a corresponding Boolean sync pref yourself and set the value to true.
  • services.sync.prefs.sync.*
There are services.sync.prefs prefs related to set which prefs to sync and you can set the corresponding services.sync.prefs.sync.xxx pref to false to prevent syncing a pref.

Thank you for replying, but that is not my issue. The problem is that NONE of the preferences/settings are syncing.

After sync the 2nd computer still has the default ("brand new firefox") settings - NONE of any preferences got synced from my first computer.

The bookmarks and addons get synced fine, but not any of the preferences.

Modified by Bogdanov89

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Bump, help still needed.

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Could you post a Sync log to see if there is a problem?

You can check the about:sync-log page via the location/address 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.

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I tried syncing on a 3rd computer, same issue - preferences did not get synced, but other things like bookmarks did. I checked "about:sync-log" on all 3 computers and there are no logs on any of the 3 computers.

I made a completely new Firefox account and tried using it to sync Preferences, but it did not help... same issue.

Does the sync preferences feature even work?! Since Firefox implemented Sync i have never been able to sync preferences across any computer.

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You can temporarily set the services.sync.log.appender.file.logOnSuccess pref to true on the about:config page to also get a log of a successful Sync. Do not forget to reset the services.sync.log.appender.file.logOnSuccess pref to false after you have finished testing Sync or you will end up with a lot of unnecessary log files.

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

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Thank you for replying. Here are a few logs from two of my PCs.

First pc logs (it has the correct preferences): https://pastebin.mozilla.org/8854969 https://pastebin.mozilla.org/8854970 https://pastebin.mozilla.org/8854971

Second pc logs (the one i am trying to sync to): https://pastebin.mozilla.org/8854972 https://pastebin.mozilla.org/8854973 https://pastebin.mozilla.org/8854974

My "configured" firefox on the 1st PC looks and behaves nothing like the "synced" firefox on the 2nd PC. If the Sync has truly been working properly all this time, it's synchronization of preferences is absolutely worthless and unusable.

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Yes, there is no evidence that Firefox is syncing preferences.

Did you check the sync settings in all connected devices to make sure that preferences are included? You probably can only sync preferences to a desktop computer.

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Thank you for replying cor-el.

I am only using standard computers with Windows 7 Home Premium or Ultimate. In about:config under "services.sync.prefs.sync" everything is set to true on all computers. In the Tools>Options>Sync everything is checked to sync except Tabs - earlier i tried enabling Tabs and they sync properly, but i do not need that feature.

Bookmarks, Addons and tabs Sync properly, but the preferences/settings never sync. What else can i do or try to make sync of preferences work?

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You would have to inspect services.sync.engine.* prefs (services.sync.engine.prefs) to see what engine are enabled. You can try to force a sync by changing a pref that has the corresponding services.sync.prefs.sync.* pref set to true.

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duplicate post.

Modified by Bogdanov89

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When i searched for "services.sync.engine" in about:config i found something strange:

"services.sync.engine.prefs.modified" is set to false.

When i try to change it to true it will change back to false automatically after a few seconds (or after i do a manual sync).

I tried changing this option to true on both my computers, but it always resets to false.

Also when i try to change that line, another one instantly appears called "services.sync.engineStatusChanged.prefs.modified" and it is set to true.

Is this relevant to my issue? From the name it does sound very relevant, but i do not know.

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Bump, help please.

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Bump, help needed.

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The "services.sync.engine.prefs.modified" line is, i think, there to control do modified preferences get synced.

On all my PCs the "services.sync.engine.prefs.modified" is set to false and it refuses to change.

When i set it to True it will auto-revert back to False! Can anyone please help?

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