Hydroxide-encrypted emails can't be decrypted by PGPy

[ajkessel]

Emails sent via Hydroxide's SMTP interface can't be decrypted with PGPy, which is apparently the only viable Python PGP library. Emails sent via any other Proton client (web UI, mobile app, official bridge) can be decrypted with PGPy. So something about Hydroxide's reliance on OpenPGP.js is different from all the other clients. Is there any easy fix for this?

Discussion of this issue on protonmail-api-client