Show HN: SecretGate – self-hosted anonymous inbox, E2E encrypted in the browser

Cool I like it but I wasn't able to setup a box, I get errors. I made a similar alternative with this ethos. https://gitlab.com/here_forawhile/tmailplus

You don't have to trust the host, cause you are the host!

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I can't find any tech details, can we find some code/paper/docs somewhere?