hi RamyEmam, the proper sync password is the only way to decrypt your sync data stored on mozilla's servers. by resetting the password you lose the only decryption key and the data on the servers is lost unfortunately (this has to be confirmed during the password reset procedure).

Thanks Philipp for your reply, yes they should warn users for this action. and they should revisit this mechanism, forgetting my password doesn't mean to lose my data.

There is a warning message about resetting the Sync Password.

See the screenshot.