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You cannot encrypt email End to End.
Incorrect.
https://support.mozilla.org/en-US/kb/introduction-to-e2e-encryption
It has to be stored in plaintext somewhere.
- It doesn’t.
- Even if it did, that wouldn’t mean it wasn’t E2EE.
Yahoo does not offer encrypted email.
It doesn’t need to. https://support.mozilla.org/en-US/kb/thunderbird-and-yahoo
Do you mean a Docker container registry? If so, here are a couple options: