Sync in Firefox 4.0 beta 7
November 12, 2010
Update: If you’ve opened this article because you want know how to file a Sync bug, please read: How to file a good Sync bug. Thank you!
Under the hood, the Sync feature shipped in Firefox 4.0 beta 7 is on par with Firefox Sync 1.5. The new setup wizard is also there, now generating accounts solely based on email addresses and the new 20 character Sync Key. There are a two of differences compared to 4.0 beta 6 and the add-on, though:
Toolbar button
As 4.0 beta 7 removed the status bar, we had to find a new place for the Sync button. Our philosophy is to make Sync a background service that you shouldn’t have to interact with. So want to impose as little UI as possible on users, but we do realize that some users like to be able to sync manually as well from time to time. So we’ve made the Sync button an optional toolbar button. It is not in the toolbar by default, but if you right-click on the toolbar and select Customize, you can drag it in any toolbar (the tabs bar, the navigation toolbar or even the add-on toolbar).
about:sync-log
Traditionally, Firefox Sync has kept a log of its actions under about:sync-log. This has been very handy for debugging problems when things go wrong. However, most of the time the logging to disk creates I/O overhead that we’d rather not have, especially on mobile devices. Logging to disk is therefore disabled by default now. You can re-enable it, for instance when you’re trying to track down a problem:
- Go to about:config
- Do right-click, select New -> Boolean
- Give it the name
services.sync.log.appender.debugLog.enabled(case matters!) - Set it to
true - Restart Firefox
(Due to an oversight the services.sync.log.appender.debugLog.enabled preference doesn’t exist by default in beta 7. That will be fixed in the next beta, though.)


November 12, 2010 at 11:29 pm
Not only there are people that wants to sync manually, Sync never autosync if the user has set a master password. I would love that sync ask me my master password automatically the first time it autosync, better if it shows the new urlbar based poopups instead of the master password dialog
November 12, 2010 at 11:32 pm
Sync *does* autosync once the user has unlocked the master password for the session, it just doesn’t trigger that prompt right now. But yes, we want to fix that and actively prompt you at the first sync.
March 13, 2011 at 3:33 pm
Actually that’s an horrible idea, nagging users to unlock the password store should be an option. Unfortunately I noticed that’s the default in Sync 1.7/FF 4 b11 and services.sync.autoconnect is not even honored. Good way to push users towards a weak master password or no password at all.
November 13, 2010 at 1:41 am
It would be nice to have a quick way to toggle sync on and off without having to go via about:config and remember pref strings. How about an about:sync page that has a button on it to toggle logging on and off, a button to say sync now, and a view of the log (and then get rid of about:sync-log I guess)?
November 13, 2010 at 2:06 am
I don’t see the need for this at all. The only time you ever need logging is when there is a problem. Sync could actually be a bit smarter about this and automatically write the log when there was a problem.
November 13, 2010 at 3:09 am
It would be nice if the icon could be animated while syncing is taking place. I miss not knowing what the hell is going on.
November 14, 2010 at 2:59 am
The Sync icon does have a very subtle animation when a sync is happening. I’m not sure how useful it would be if there was more visual feedback, I think it would just be distracting. As said in the blog post, the philosophy of Sync is to be a background service. It *does* surface error messages, but so long as everything’s working fine, why distract the user unnecessarily?
November 14, 2010 at 11:19 am
Currently there is in fact some rather noticeable (and annoying) ‘feedback’ while sync is happening, as someone has already detailed here:
https://bugzilla.mozilla.org/show_bug.cgi?id=576651
November 13, 2010 at 1:40 pm
In my opinion the Sync icon looks to much like a reload icon. Especially in these places.
December 21, 2010 at 9:25 pm
It does, now that I think about it. The old Weave icon (it looked kind of like a 2×3 Celtic knot) would be a lot more difficult to confuse.
November 13, 2010 at 1:40 pm
I’m a little worried that the button looks too similar to a refresh button.
November 15, 2010 at 3:20 pm
I love sync and I love that it just works in the background without me having to do anything.
But it’s almost too quiet. There’s no easy way to see status … When I installed it on a new machine recently, there was no obvious visual way to see if it worked. (Until I went to a page where it knew my password.)