Yep. Not sure how Apple/Proton implement it, but that's exactly what Tutanota does. https://tutanota.com/blog/posts/first-search-encrypted-data https://tutanota

Yep. Not sure how Apple/Proton implement it, but that's exactly what Tutanota does. https://tutanota.com/blog/posts/first-search-encrypted-data https://tutanota.com/blog/posts/first-search-encrypted-data