User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/110.0

Steps to reproduce:

Log in to an already existing Firefox account and sync.

Actual results:

Firefox correctly imported most of the configuration, including the already installed extensions, bookmarks, and sites pinned to the newtab.

However it did not import settings within the extensions (ex: missing previously created Ublock Origin settings and filters, missing dark reader per-site settings as well as global configuration, and even Firefox's own multi-account containers created on other device).

It could not fetch configuration regarding the previous settings for the items within the toolbar (with the exception of bookmarks which were brought as they were).

And it also added sites that had been previously unpinned from newtab back to it (facebook, reddit, twitter, amazon).

Expected results:

Firefox should have fetch configuration of the extensions, the configuration of the toolbar, and not modify newtab if it had been previously tweaked.

The Bugbug bot thinks this bug should belong to the 'Core::Widget: Gtk' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Thanks for the report. Many of these issues already have bugs filed:

(In reply to tomarvu from comment #0)

However it did not import settings within the extensions (ex: missing previously created Ublock Origin settings and filters, missing dark reader per-site settings as well as global configuration

Generally extensions need to opt-in to syncing their settings by using the browser.storage.sync API, and best I can tell, UBlock does not.

and even Firefox's own multi-account containers created on other device).

There are a few reports of this too - see https://github.com/mozilla/multi-account-containers/labels/Component%3A%20Sync

It could not fetch configuration regarding the previous settings for the items within the toolbar (with the exception of bookmarks which were brought as they were).

This is bug 943182, however it's unlikely to ever be done, because often people want different toolbars depending on the size of the monitor on the device.

And it also added sites that had been previously unpinned from newtab back to it (facebook, reddit, twitter, amazon).

This is being tracked in bug 1497038

Bug 1269548 is where we are tracking all feature requests for additional things to sync, so I'm going to mark this as a duplicate of that.