A few weeks ago I began work on modifying the cookie system on Firefox to support multiple “containers”. Multiple Containers enables users to log in to many websites as multiple users on the same Firefox session. It is very useful for web developers who require this functionality to test their user account systems. Another use is for people who have multiple web mail accounts with the same provider that they want simultaneously logged on to. This is an oft-requested feature that Internet Explorer partially supports. (See bug #117222)
I’m happy to say that this is now ready for testing. Below is a working build for Windows. It is based on the latest Trunk plus the cookie patch and extension. Unfortunately for Mac and Linux users that wish to try the patch, they will have to manually compile Firefox with the patch below.
Note that this build is meant for users who are familiar with using Firefox test builds and not intended for production. You are recommended to create a new profile. If you intend to use an existing Firefox Trunk profile on the cookie patched Firefox, the only caveat is that your old session store (windows and tabs saving) cookies will not be restored (but long term cookies will be there). Similarly when transitioning back from the patched Firefox to normal Firefox, you will lose the session cookies, but also will be unable to access cookies saved in containers other than Jar A.
In the patched Firefox, to use the new container, or “jars”, just click on the jar icon in the far right of the status bar. The letter represents the current selected jar for this tab. You can assign a different jar letters to each tab. Cookies from all accessed pages will be deposited in this jar. If you open a link in a new window/tab, the jar letter should carry forward to the next window/tab.
All long term cookies are saved in the Firefox profile folder. Jar A will be saved as cookies.txt and compatible with older Firefox. Jar B will be saved as cookies_B.txt and Jar C cookies_C.txt
There is a known issue in which if you have the cookie manager open while browsing, it will incorrectly show cookies listed. This is just a GUI issue and doesn’t affect the core functionality.
To compile with the patch yourself, download and apply the patch the trunk (made against 13-May-2007). In the compiled result dist/bin extract cookiejarschrome.zip into the chrome subfolder.
Edit: Fixed links