Mozilla announced that it’s bringing a new feature to Firefox 50 Nightly, which is designed to help users easily separate their personal, work, banking, and shopping browsing habits on a per-tab basis.
The main idea behind Mozilla’s contextual identities is to separate into different containers data from websites that you may visit for personal reasons from that of work-related browsing. Banking and shopping data can also be kept isolated in their own containers, which should increase the security of that data.
For instance, if you visit a malicious site in a non-Banking container that tries to to steal your financial information, it won’t be able to access information such as the financial site’s authentication cookie that resides in the Banking container.
Each one of these containers will get its own separate cookies, indexedDB, localStorage and cache. A Personal container wouldn’t be able to access data from a Work container, but multiple Personal containers would be sharing the same cookies, cache and local databases.
By default, Firefox’s New Tab and New Window functions will work as usual, as “generic containers.” You would have to manually create a Personal, Work, Banking, or Shopping container. These custom containers can be created from the File menu or from Firefox's "hamburger" menu.
These container tabs will be color coded so you don’t confuse them with the generic tabs in Firefox, and they’ll also be labeled at the end of the address bar. You can create as many tabs of the same type of container as you want.
Mozilla believes that these containers should improve the browsing experience for people who were logging into Twitter or other sites from two different browsers to keep the identities isolated. Containers are also a middle ground between visiting all websites in the same browser and using the Private Mode, which deletes all data on exit.
Mozilla also noted that its goal with containers is to improve privacy without breaking site functionality, but tracking may still be possible through the use of fingerprinting (from data such as OS, user agent, IP address, etc.). To protect against that sort of fingerprinting, the Tor browser (which is based on Firefox) would be a better choice.
Lucian Armasu is a Contributing Writer for Tom's Hardware. You can follow him at @lucian_armasu.