I have seen many dozens of similar bookmarks "corruption" threads over the last 4 1/2 years, and the one thing that most all have in common is Firefox for iOS or Firefox for Android being involved in the Sync 'chain'. I have even seen a few support threads that involved over 100 sets of duplicates, where the user didn't catch the duplicates for quite a long time.

IMO, that iPhone iOS 13 device is causing that corruption within Sync. But if that iPhone iOS 13 was "playing nice" before you restored the back up file, perhaps that back up was corrupted.

BTW, Sync handles bookmarks for the "Firefox for ..." mobile devices a little differently than Sync handles bookmarks for the laptop & desktop versions of Firefox. For what I have read the Mobile bookmarks system on the Sync server is what differs from the Desktop / Laptop versions of Firefox.

Hello the-edmeister

thanks for your reply i will try disabling bookmarks sync on my iPhone and see if that helps. I will wait a day or two and try sync in my laptops and see hat happens.

i will post again once I've tried this

thanks again

Hello,

i have tried disabling sync on my iPhone iOS 13, i have waited a couple of days, but then when i have accessed Firefox on my Windows 10 laptop (and then as well on my mac book) the same problem with duplicated bookmarks occurred.

If this means that my original backup file is corrupted, is there anything i can do to fix it? Just for clarity, when this issue occurs, i do NOT normally restore bookmarks from the backup file, i go to the bookmarks library and then choose Import&backup>restore>pick the date with the correct bookmarks

i have, of course, restored form a backup file sometimes in the past, so maybe this is what originated the issue?

Again, any further suggestion would be much appreciated

thanks

One thing I forgot to mention is that with Sync there is no "primary" or master device. All carry the same weight, although "Mobile" does have a few different features than "Desktop / Laptop" devices; "Mobile" is lighter in the browser and heavier at the Server.

1. On both Windows devices, disconnect from Sync at the same time, and restart Firefox on both devices. And on the MacBook, too.

2. In Help > Troubleshooting Information -> way down that listing - Places Database - Integrity use the Verify Integrity button and wait for the report results to appear. Then highlight that information and copy it; paste the info into a text file and save it. At this point we may not need it, but just-in-case this issue persists. Do that for all desktop / laptop devices. Mobile doesn't have that "Verify" feature in the UI, from what I understand.

3. Once you're done (and iOS 13 is still disconnected from Sync) got to Manage Accounts thru Sync - Options / Preferences (or via this URL) https://accounts.firefox.com/settings and Change ... your Password for your Firefox Account. That will clear your Sync data from the Sync server; a notification of such will appear for your approval to proceed.

4. Then start to proceed slowly connecting all your devices (except for iOS 13 at this point).

A. First start with the device that you use the most (? "Primary" or "First used"). Let that Sync connection proceed for quite awhile, and restart Firefox a few times to allow for a "launch" connection with the Sync server. Be aware that Sync may work in "spurts" of activity at times when "your Sync server location" is loaded and if the user is re-arranging bookmarks it will switch to a "batch mode" {disconnect from Sync if you are going to move more than just a few bookmarks.}. Sync is fast, but it's not 'fast' like when downloading data or application files from a download server. The Sync server is more complicated with more 2-way exchanges of data, especially when your Sync account is empty or when new devices are first connected.

B. Check that the 'multiple copies of bookmarks' hasn't happened again before connecting 2nd and subsequent devices. Catch the "faults" as soon as they happen.

C. Delay connecting that iOS 13 device to make sure the base issue is corrected. I can't "test" Firefox for 'mobile' and don't trust Sync on 'mobile' based upon the continuing number of issues that I see here. Yes, a lot better than 3 years ago and Sync use is a lot greater in the last 1 1/2 years, or so; but my trust hasn't been restored - as a "by-stander" who just bought their first smart phone.

Hopefully you will get that 'duplicates' issue solved.

Hello,

i have tried as you suggested above and it seem to work now after few days, i have reactivated sync in all my devices one a few days after another and i keep the iOS with sync excluding bookmarks to be safe.

Also, and i had totally forgot about it but it may well be one of the things creating the problem, i remembered that i had a Firefox add-on, (active but hidden, so i forgot all about it) to sync bookmarks from Firefox to icloud/safari. i have now deleted this add-on as i don't use safari in any device.

In any case, bookmarks are not duplicating since few days so problem solved. and thank you very much for you help!

maurizio.pim said

.... Also, and i had totally forgot about it but it may well be one of the things creating the problem, i remembered that i had a Firefox add-on, (active but hidden, so i forgot all about it) to sync bookmarks from Firefox to icloud/safari. ....

Yep, using iCloud bookmarks along with Sync is another potential cause which some users have reported.

Glad you got it fixed!