My metamask extension can't be accessed after Mozilla firefox version has been updated to the latest one. The wallets created on metamask before it was updated couldn't be seen and I can't open it even though I used to downgrade the firefox version. This is my biggest problem nowadays, so I am hoping those technical buddies here who can give me possible solutions.
Your first mistake was to use a browser extension as a wallet.
For the future, just use a proper wallet instead of some stupid browser extension to store crypto.
Regarding your problem.. what happens when you downgrade firefox to a version where your extension worked? It simply doesn't work either?
You might want to open an issue on github:
https://github.com/MetaMask/metamask-extension.
The situation is very stressful for me, I got some tokens in there which I never been backed up particular with seed phrase.
This was your second mistake.
You always need to have a backup. There are so many scenarios which could have led to a loss of your crypto.
After your problem gets fixed, i would recommend, that you switch to a real wallet and create at least 2 (non-digital) backups of your mnemonic code before continuing using crypto.