Feature Request: Support in-page encrypted email detection

Other, less popular chrome extensions such as "Mailvelope" have a very helpful feature where they detect PGP encrypted blocks in an open email in, say, gmail, and prompt the user if they would like to decrypt and verify the sender of the message, within the gmail page. I wouldn't mind if it requested my encryption passphrase, or had to pop up a separate overlay with the message to isolate it from malicious code within the target website, but this would do a lot to help me manage PGP encrypted emails, thus helping further promote PGP use in everyday communication. Specifically, i have the Cryptocurrency exchange Kraken send all my account management emails encrypted so that compromising my gmail will not allow a password reset, or any other changes, and it is somewhat annoying to have to open up a whole new tab, login to Keybase, and paste into the decryption page to read the email. it is even more of a pain to use the Keybase CLI. You already have the bulk of the code implemented in a browser friendly language, so would you consider implementing this feature?

The request names Gmail, Mailvelope, the Keybase web decryption page, and the Keybase CLI, but identifies no repository file, entry point, or test. First map the existing browser-facing code mentioned in the request; the issue is complete only when the supported in-page detection, decryption, and sender-verification behavior is defined and covered.