"To determine whether your browser supports 128-bit encryption, select Help/About from your browser menu. Most browsers will display the phrase ?128-bit encryption? or "128-bit cipher strength.? If you are unsure whether your browser supports 128-bit encryption, contact the software company that developed the browser."
But I can't seem to find this information on the about page or in online articles about encryption. Would you please help?
The Firefox browser uaseragents used to have a U to denote it is a browser with strong encryption and this was removed as of Firefox 4.0. It was removed as it really was not needed anymore anyways for several years now and the browser we know as Firefox supported 128-bit if not 256-bit since it was Phoenix 0.1 back in Sept 2002. Yes the browser was out for two years before the so called November 9 2004 release date.
128 bit is the minimum that you can use with Firefox and you can only go higher (e.g. 168 or 256).
128 bit shouldn't be used these days and servers that only support 128 bit should update their software.
Firefox supports AES-256 since 2002, so that is already more than 10 years.