on an IPAD,
login does not work at all from Firefox. It just sits there.
chrome works pretty well, but the presentation some times gets into a state
where necessary things are not visible. The biggest problem is that there's
no way to "click right" to see a card when it could be played by clicking left.
I'm not sure about the login for Firefox, does it sit in the login screen and you can't enter credentials, or does it do nothing once you hit "Login"?
Right clicking on touch devices is done by a "long touch", that means you don't remove your finger from the surface and after some time (I think a few seconds) it will do what right-click does.