application network protocol.
Firefox Sync can synchronize between your own Firefox web browsers over different devices for the following:
- Bookmarks
 - Opened tabs
 - Passwords
 - History of browsed web pages
 - Add-Ons (not available on mobile devices)
 - Preferences (not available on mobile devices)
 
Application Program
Setup by GUI
Setup by command line
On the UNIX platform, Firefox stores its preference data settings in the
$HOME/.mozilla/firefox directory. Check for your specific profile
subdirectory in the $HOME/.mozilla/firefox/profiles.ini file.
Add the following lines to the user.js file.
Notice: Any and all changes toward ``preferences.js`` will be blown
away by the next Firefox upgrade.
| Column | Description | 
|---|---|
| prefs.js:user_pref(“services.sync.username” | johndoe@example.com”), The Sync account name (maintained by Firefox Account Manager) | 
| prefs.js:user_pref(“services.sync.declinedEngines” | “tabs,addons,passwords,history”); | 
| A list of things to keep track of. Valid options are tabs | addons, passwords, history. | 
| prefs.js:user_pref(“services.sync.account” | “johndoe@example.com”); | 
| prefs.js:user_pref(“services.sync.client.name” | “johndoe’ Firefox on johndoe-macbook”); | 
To set up the
Firefox Sync Network Protocol
Firefox Sync Server
To host a private server of Firefox Sync, see [https://mozilla-services.readthedocs.io/en/latest/howtos/run-sync-1.5.html%7CHowTo Firefox Sync server]