On my Ubuntu 14.04, there is a Firefox extension "Ubuntu Online Accounts 0.5", installed by the package xul-ext-webaccounts
(which is in the default install).
What is the purpose of this extension? What will stop working if I disable it?
There seems to be no documentation in the package, the description page of the extension is basically empty, and the only link points to https://launchpad.net/webaccounts-browser-extension, on which I also cannot find information on its purpose.
Of course I suspect it is related to the Online Accounts dialog in the System Control Center, however Firefox is not listed as an application in that dialog, and when I visit a page such as Twitter with Firefox for which I have an account set up under Online Accounts, nothing happens.