User name and password are stored correctly in preferences, but the fields remain blank whenever I try to login to a site I use often. No prompt "Do you want firefox to remember..." Do get a popup "do you want to update password?" but it makes no difference whether I check yes or not.
No such problem with several other sites whose passwords are stored.
You must have the "Remember passwords" feature enabled for the browser to remember them. In Firefox 2.0 and above, make sure Tools -> Options -> Security / Passwords -> "Remember passwords for sites" is checked. Additionally, you may have once told the browser to never save the passwords for the site. In Firefox 2.0 and above, check the list under Tools -> Options -> Security / Passwords -> Exceptions. Also make sure you are not private browsing while saving password.
Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance).
Websites may be using autocomplete=off to prevent Firefox from saving form data like name and password.
You can remove autocomplete=off with a bookmarklet to make Firefox store form data like names and passwords.
Note that Firefox won't auto-fill saved form data automatically when autocomplete=off is used, so you need to double-click the empty name field to get a drop-down list.
I've done this, but problem persists. Just with that 1 site. And Firefox used to remember! Seems the issue arose after an upgrade. (I question the term.)
This can be happening because some website block the autofill using the attribute autofill="no" in the HTML code, you can use an addon to get the fills in this kind of website:
i think this is a bug with the pref signon.storeWhenAutocompleteOff. it is simply not filling in passwords on sites that have autocomplete set to off.