Here's why I won't use it if I have any other option: As an example to see if it's still an issue -- I tried clicking your islington.cc "sign-in or register" button. I'm greeted with a popup saying "We are sorry, but currently your browser is not supported. <firefox logo> Persona works with Firefox and other modern browsers". The browser I'm using? Firefox (ESR 24.whatever is current). Closing the pop-up and trying again worked, eventually. This happens about a third of the time I try to use a persona-based sign-in.