When I try to login to Twitter, either through their main site or through an app trying to access Twitter, and enter my correct credentials, I am sent back to the login screen. I have cleared my cache and history, I've reset my Twitter password, and I've tried running it in safe mode. Nothing works. I can access Twitter on other browsers (Chrome and Internet Explorer), but Twitter doesn't work for me on Firefox at two different locations (work and home) with two different IP addresses.