I've noticed for a while that I have to manually log back in to websites frequently even when I check "remember me" to enable permanent or long-lasting cookies. I always thought it was an extension causing the problem, but recently I reinstalled my OS (Arch Linux) and it happens on the latest Firefox (30.0) even with no extensions installed. For one website that exhibits this problem, Hall.com, I even reached out to them about it but they couldn't find any problem on their end. After logging in, there is a rembember_user_token cookie that is set to expire in 3 years. Is this a bug, or could there be anything else preventing the cookie from being stored?
It seems to have been this issue:
Firefox does not remember login information1
It may be due to a corrupted
cookies.sqlite file in Firefox's profile folder. In order to fix this, just rename or remove
cookie.sqlite while Firefox is not running.
Open a terminal and type the following:
cd ~/.mozilla/firefox/xxxxxxxx.default/ rm -f cookies.sqlite
xxxxxxxx represents a random string of 8 characters.
Restart Firefox and see if it solved the problem.