- You can self-host your own sync server. It's not something we spend a lot of time making easy, but it is possible and supported in some capacity: https://mozilla-services.readthedocs.io/en/latest/howtos/run...
- You can definitely build extensions for other browsers (or a standalone app) that implement the Sync protocol.
In fact, GNOME's web browser already did so: https://blogs.gnome.org/mcatanzaro/2017/08/09/on-firefox-syn...
EDIT: Forgot to mention Weave was exciting because you could integrate with other browsers. And there was a Dolphin add-on which did just that.
I've never understood why someone didn't implement a Firefox Sync extension for Chrome or vice-versa. Is it technical or are people opinionated enough about browsers that no one has the personal need to develop such extensions?
(It’s also going to be very difficult to implement a robust sync system this way, integration with the underlying storage is all but required for that)
The real problem is data model is significantly different. It's possible, but a lot of boring work, designing the appropriate transformations.
https://superuser.com/questions/614744/how-to-set-up-a-own-c...
- It can be integrated into Google Chrome on desktop operating systems.
- It can be provided as a stand-alone app on iOS so that I can:
a) “Share” links to this hypothetical stand-alone Sync app from Safari in order to send them to Firefox Sync bookmarks storage.
b) Copy username and password from the stand-alone Sync app when using Safari on iOS.
It might sound like a peculiar setup but bear with me.
The situation is that I run Firefox as the main browser on my laptop, Chromium as main browser on desktop and Safari as main browser on iOS.
For a long time I’ve used Firefox Sync as the “main” storage of passwords, and I would go into Firefox settings and copy username and password from there on desktop and mobile. Even though I store the passwords and usernames in the other browsers on first login it’s still a bit cumbersome whenever I add a new account, log in for the first time, or change a password.
Recently on desktop I started using KeePassXC on my desktop and the browser plugins for it in order to make it a bit smoother. Today I installed MiniKeePass on iOS and am going to find a good way of keeping it in sync with my desktop. In the end though, KeePassXC is not quite what I want, whereas the core of Firefox Sync is exactly what I want.
As for my bookmarks, they are all over the place. Some in Firefox, some in Chromium, some in Safari, some in exported files or copies of old homedirs, and a lot of bookmarks probably lost at various points in time. Again, the core of Firefox Sync is what I want.