Hacker News Reader

Which support custom domain and more features, and not locked to a specific browser.

Both open source and self-hostable, SL is by Proton(Mail).

DDG email protection isn't locked to a single browser, I've been using it on Chrome/ium and Firefox for around a year now.

I meant on mobile, you can't use it without using DDG browser.

Same, it is not available on Safari though.