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How do I know that sync has completed successfully and that it is safe to close the browser?


I work either on my desktop PC or on my notebook. The latest Firefox is installed on both computers (FF10.0)

(1) I am not sure whether I have to start sync manually (tools/sync now) or if this is taken care of automatically on an ongoing basis.

(2) In any case, how do I know when sync has been completed successfully and it's safe to close the browser.

I just don't want to find myself on the road with my latest password updates or bookmarks missing.

I don't see any status info about the sync process. This is very disturbing and not exactly implying trust.

Yours John

Chosen solution

Maybe check the Sync log on the about:sync-log page page
You can open about:xxxx pages via the location bar like you open a website.

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Additional System Details


  • User Agent: Mozilla/5.0 (Windows NT 5.1; rv:10.0) Gecko/20100101 Firefox/10.0

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  • Top 25 Contributor
617 solutions 4263 answers

See: What is Firefox Sync?

and: How to sync Firefox settings between computers

thank you

Question owner

Ideato, I appreciate your answer, I have read those pages before and looked at them again. I still do not know when sync has been completed successfully. Probably there is no way to tell. Thanks.

  • Top 10 Contributor
  • Moderator
10752 solutions 96760 answers

Chosen Solution

Maybe check the Sync log on the about:sync-log page page
You can open about:xxxx pages via the location bar like you open a website.

Helpful Reply

Excellent, cor-el!

That works for me.

about:sync-log provides a list with log files and shows the location where they are stored in the firefox profile on the harddisc.

By default it shows only errors though. Depending on how long you have worked without syncing it can take up to a couple of minutes to be completed.

Luckily you can configure Firefox that it writes log files on success as well. Then all one has to do is hit reload on about:sync-log and wait till the success log file appears or gets appended.

There are a lot of setting that effect the sync process. A lot of timeouts and those kind of things,… I guess it's better not to tamper with most of them. :-)

However, here's the trick that lets Firefox create/write log files on sync success as well.

Type about:config and be super careful when changing anything.

The parameter in question here is services.sync.log.appender.file.logOn Just type that into the filter and two keys will be shown.

services.sync.log.appender.file.logOnError default true services.sync.log.appender.file.logOnSuccess default false

Change the latter one to "true" and keep an eye on the list shown when typing about:sync-log in the location bar.

Delete some of the files (in case this doesn't happen automatically—I did not check) once you'll have got too many of those.

Thanks again, co-rel

As you can see your answer was super-helpful.

Yours John

P.S.: It's good to know this stuff, since I checked and had sync time from start to finish anywhere between 20 seconds and 4 minutes (and I am on fast high speed). It's really easy to shut down the computer too early. It's a good idea to always issue a manual Sync Now command when you know that you'll switch computers.

Modified by John