Go to Options (either from the Tools menu or the Hamburger), Privacy & Security, click "Saved Logins...". In the new tab on the bottom left is an option to manually create logins.
Did you look at the uploaded picture? there is no "Add credentials". But there actually was a solution.... There is an Ff add-on to save passwords, with a link that appears in the address bar. If you click it after filling in the login, it will finally make the firefox pop up appear (top left) that asks if you want to save the login, and it then is...
why always make life so difficult A few clicks and everything is fine Open the menu at the top right (the three lines) Access data and passwords (bottom left) Add credentials (click)
First of all, what Joe C says happens to be the reality. The other thing is, that f.e. one can use an OLD Ff without the telemetry garbage like 52.9, or, block Mozilla in the FIrewall And, just by the way.... should someone take over my computer... that this person (or government) maybe reading my mails, will probably be one of the minor problems. What I find puzzling is, why on both my computers "Add new login" does not appear... One uses the updated Ff esr and one another Ff, yet on both no add new login, as the picture I uploaded shows....
Well, that might be the actual meaning of the exercise - using a Firefox version of before it became complete crap.