Mozilla and the email development team client Thunderbird released version 78.2.1 on the fixed channel last night. Existing installations of Thunderbird will be automatically upgraded to the new version, provided that the mode automatic update and you have it installed version 78.x.
One of the big new features of Thunderbird 78 was support for PGP encryption built right into the application. The users of Thunderbird, previously had to install extensions like Enigmail to have PGP support.
The release of Thunderbird 78 had built-in support for OpenPGP, but was not enabled by default due to some issues that needed to be resolved.
The release of Thunderbird 78.2.1 allows OpenPGP support by default in Thunderbird. Choose Tools> OpenPGP Key Manager, and you'll see available keys that were previously created or imported, and options for creating new keys that can be used to encrypt your chats via email.
Clicking Generate> New Key Pair starts the process. All you have to do is select one of your available email accounts and click on "create key" to create an encryption key.