This may not work for every version of Firefox and/or Metamask.

This only works if you know the password of your wallet.

This only works if you can still have the data folder of the Firefox installation that held your wallet.

1. Make sure you have Python 3 installed

2. Install the python packages python-snappy and python-cramjam

3. Browse to your Firefox data folder (you may need to show hidden files)

   On Windows it's likely to be here: C:\Users\[USERNAME]\AppData\Roaming\Mozilla

   On Linux it's likely to be here: /home/[USERNAME]/.mozilla

4. Download this repository's script:

   https://raw.githubusercontent.com/JesseBusman/FirefoxMetamaskWalletSeedRecovery/main/firefox_metamask_seed_recovery.py

   ... and put it in the Firefox folder

5. Open a terminal, command prompt or powershell in the Firefox folder

   On Windows: Shift + Right Click on the Firefox folder -> Open command prompt or PowerShell here

6. Run this command: python firefox_metamask_seed_recovery.py

7. If successful, something like this will be displayed:

   ---------------------------------------
   Probably found a Metamask vault:
   
   {"data":"m9b27bSJDFv5svrd7r76v/98nnv678b4TG6v8m+k0v998vnFf98nvfd9f==","iv":"8bbsvdG/G453==","salt":"AS6D/faas+8JJSD="}
   
   ---------------------------------------
   

8. Copy everything from the { up to and including the }. Metamask calls this the 'vault data'

   On Windows: Click and drag to select, then press Enter to copy

9. You can now use the Vault Decryptor: https://metamask.github.io/vault-decryptor/

   • Download these two files and save them in the same folder:

     https://raw.githubusercontent.com/MetaMask/vault-decryptor/master/index.html

     https://raw.githubusercontent.com/MetaMask/vault-decryptor/master/bundle.js

   • Recommended: Disconnect your computer from the internet

   • Open the index.html you downloaded and use it to recover your wallet seed

   • When finished, close the Vault Decryptor browser tab and delete the index.html and bundle.js files

   • You may now reconnect to the internet

   If the vault decryptor gives you a 'Problem decoding vault' error, try using an older version of the vault decryptor by downloading these two files instead:

   https://raw.githubusercontent.com/MetaMask/vault-decryptor/186101b5d7047aabc2d04455bbaa103f9f3c425a/index.html

   https://raw.githubusercontent.com/MetaMask/vault-decryptor/186101b5d7047aabc2d04455bbaa103f9f3c425a/bundle.js

Good luck!

Tips: 0xC5e9aCcd70FaEdafbe28D8b83DCCf5d3E9C8E527