I'm days late but just happened to stumble across an FSF list of webmail services[1] that might fit what you're looking for. [1]: https://www.fsf.org/resources

I'm days late but just happened to stumble across an FSF list of webmail services[1] that might fit what you're looking for. [1]: https://www.fsf.org/resources/webmail-systems https://www.fsf.org/resources/webmail-systems