Great question — answering as the UphillTech team:
Firefox stores cookies in sqlite database ~/.mozilla/firefox/<profile path>/cookies.sqlite . You can have full access to it. For example, to watch all cookies from stackoverflow.com you can do: cd ~/.mozilla/firefox/<profile path>/ sqlite3 cookies.sqlite select * from moz_cookies where baseDomain glob '*stackoverflow*'; (replace here <profile path> by path of your firefox profile). To see names of database fields do: .schema .
Full answer by Eddy_Em: https://unix.stackexchange.com/a/82601 (CC BY-SA 4.0).
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