Just a short test with Nextcloud.
A lot of bookmarks were shown, but the most important were gone.
Not really usefull in practice.

As an open source project, wanted to like Floccus so much, but serious issues affect data security and privacy.

Namely, some users express dismay that ambiguous sync setting have seen years of bookmarks disappear.

From a privacy perspective, there is also an issue raised where bookmarks are synced in unencrypted plain text.

https://github.com/floccusaddon/floccus/issues/1427

The author has explained they are too busy to address issues and as an open source project invited others to not just raise issues but also help fix them.

Fair enough, but for now this addon should not be used by those concerned about unintended data loss or privacy.

Es mag ja sein, dass die funktioniert, immerhin soll sie - auf dem Papier - Chromium und Firefox verbinden.

Aber, der Einrichtungsvorgang, und die verschiedenen Fragen nach der Ordnerstruktur, haben sich mir nicht erschlossen, und dass führte letztlich dazu, dass auf meinen beiden Rechnern, deren Browser ich mit meiner Nextcloud-App synchen wollte, ALLE TAPS, JE LESEZEICHEN-ORDER geöffnet worden sind, was meine Maschine fast hätte zusammenbrechen lassen.

Ich habe zuletzt, bei der Einrichtung eine Auswahl getroffen (Reiter synchen), von der ich hoffte, dass keine Lesezeichendatei angelegt werden muss, sondern nur die Reiter abgeglichen werden.

Lange Rede, kurzer Sinn: ich bin normal blöd/ klug und habe es nicht hinbekommen (trotz Versuch die Schritte der Einrichtung auf http://floccus.org/ zu befolgen.

Messing with this for an hour or so and cannot get it to sync with Nextcloud. No errors, no warnings, no sync.

Syncing from one browser seems to work fine but the floccus.export.json file does nothing when I try to add my account to other browsers. There is no info oin the FAQs on what to do when this process doesnt work wither. A sync file that doesnt sync between browsers is no use to me.

Such a pain for nothing and very sad to write a bad review. I'm using Nextcloud 19 and Nextcloud Bookmark 3.4.9 with floccus 4.5.0. The first sync process load very heavy the memory of my firefox 78.8.0 ESR (more than 3Gigabytes with one empty tab open !) and of course Firefox is lagging/unusable during the syncing process. After one hour the sync is done, but not usable to another computer. On the other computer with Firefox, I can see only empty bookmark folders. I tried to read the user guide and FAQ but nothing clear. I start to think this add-on is not made to sync bookmarks accross other Firefox, it loads too much Firefox and sync is too slow (my Nextcloud serveur work flawlessly).

Floccus tried to delete bookmarks now the second time, it stopped because
E029: Failsafe: The current sync run would delete 100% of your bookmarks. Refusing to execute. Disabled this failsafe in the account settings if you want to proceed anyway.

Bookmark app floccus is not fit for production. I deinstalled it again.

Great concept and pretty interface.

Sadly, it deleted bookmarks during sync. Even deleted bookmarks on the SOURCE machine in a 1-way sync. The developer doesn't think that's important. Oh well.

Not working with Nextcloud at all, trying to sync my bookmarks is just a mess and I ended up losing all of my bookmarks... Not good.

Be extremely careful with this add-on. It worked great for about a week. However, when I woke up this morning, ALL of my bookmarks have been permanently deleted (was using this with Nextcloud). Folder structure was preserved but all bookmarks are just gone.

Thankfully, I have backups of all my bookmarks across the machines I was using this on. Will only have permanently lost a few things that I can recover.

If you really must use this add-on, make sure you BACKUP everything and make periodic local backups. I have no idea why it did this, there is almost no logging either in the floccus add-on or on Nextcloud. The documentation and support for this is pretty poor (though I do understand that it is maintained mostly by one person). I would highly recommend using something else, since this type of error is completely unacceptable for an app like this.

Maybe it works better if you self host or use only local options? I don't care to risk it again at this point.

Worked for a few weeks. Then after a Nextcloud update all bookmarks were gone.

sync with Nextcloud - NOT WORKING;
sync with WebDAV - NOT WORKING

UPD: v4.4.7 - can't push bookmarks on server - return many errors `Syncing failed with E015`. In logs private data - I send it via e-mail

Addon installation on Firefox works and login into Nextcloud works as well ... on NC "Bookmarks" is installed and works ... Floccus says sync worked all fine but nothing was synced

Update 14.10.2020: tried again for 2 hours to get it to work - no chance. Heaps of cryptic error messages but I'm ending with messed up bookmarks and have to revert to backup ...

This add-on made a mess of my bookmarks. It did not respect my bookmark folders or order, and ignored the folder I told it to make on the server side.

Nice try, would have loved to use it, but it is useless as it is now.

Beim Versuch meine Bookmarksammlung mit Floccus und Nextcloud zu synchronisieren, bekomme ich eine völlig unverständliche Fehlermeldung:
Error! invalid Bookmark: {"guid":"mobile______"}
Diese Art von geheimnisvolle Fehlermeldung, die nicht zurückzuführen ist auf ein konkretes Lesezeichen, ist ein absolutes NoGo. Eine Fehlermeldung, die nur für den Programierer zu deuten ist, hat in ein Userprogramm nichts zu suchen. (Auch ein "invalides" Lesezeichen liegt in klartext vor, und kann als solches gezeigt werden!

Fill in credentials, hit the 'Save' button, nothing happens at all. Pretty useless.

Does not work for me. I fill in the settings and hit save. Nothing happens.

Running Firefox 56.0 on Linux Mint 17.1