Lesson learnt the hard way: Always store your passwords. Yes, do it securely, use a password manager, hide a piece of paper behind multiple protection mechanisms, but DO KEEP A BACKUP OF YOUR PASSWORDS
Long story short: I decided to store every 2FA revocation code as well as every PGP and SSH key of mine in a strongly (64 Argon2d rounds) encrypted KDBX v4. As you may have guessed, I forgot the password. I do remember it slightly, but to no luck. Have been trying to brute-force it for 6 hours...
After 6 hours of running my bodged Python code on ca. 5k possible combinations, I think it's time to give up and just regenerate my 2FA revocation keys. Luckily, PGP and SSH keys were there for backup and are also present on my machine.
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