What does Firefox Sync mean?
Firefox Sync is a browser enhancement set previously known as Mozilla Weave. This browser add-on allows users to store encrypted personal data on Firefox servers and prohibits any outside party, including Firefox, from accessing the data.
Techopedia explains Firefox Sync
Sync allows for the storage and synchronization of preferences, bookmarks, address lists, calendars, cookies, browsing history, passwords, forms history and recently opened tabs. This data can be shared with others selectively, and can include a wide variety of application programs.
Firefox Sync also includes special functions for online backup, archiving and tabbed browsing.
Data synchronization occurs via an intelligent scheduler to optimize performance between the user’s browser and server; secure data transmission is ensured through WebDAV and HTTPS. Encryption, authorization, and authentication provide data privacy and security.