Use SSH in Firefox with FireSSH
After it is installed, you run FireSSH by selecting Tools -> Web Developer -> FireSSH. You will then get prompted for SSH credentials as depicted below.
To import SSH settings in .dat file format, at the FireSSH login prompt choose Tools -> Import.
When you initiate an SSH session with a host for the first time, you get prompted regarding the server’s key like so.
When you get your authentication squared away, you are presented with an SSH terminal within a Firefox browser window.
To configure FireSSH’s options, go to Tools -> Add-ons -> Extensions -> FireSSH Options.