Hi, this is Firefox Support and Mozilla has nothing to do with Blockchain, wallets or bitcoin or other currency. If you lost your key, it is lost, your wallet will stay there until site dies as will any coin/s.

So this is the wrong place to be asking for help. I hope the above answer is what you wanted.

Unless I do not understand your question. If so you will need to provide more information. If this was a extension you were using would then say please see the Developers website for help.

Please let us know if this solved your issue or if need further assistance.

You need to contact private key support.

In the event that the passwords information is lost, you should record all information in a separate text file somewhere else on your hard drive, or written down. You can easily copy and paste if you need to do so. If you are concerned about someone else looking at that file, you can compress it using a password.

Maybe you can find an answer in this thread - if not : you could post your question there.

https://bitcointalk.org/index.php?topic=1971789.0