Should I use ProtonMail?

Searching is Proton’s main shortcoming.

For starters, ProtonMail can only search for metadata, such as sender, receiver, subject, etc. Content is not searchable without enabling local content search. This is a compromise because servers in the Proton company can’t decrypt the content of your emails.

Next, ProtonMail doesn’t have an advanced search ability as GMail does. There is no such search expression syntax to search for emails with a label, within a folder, within trash, etc. In certain situations you can search folders for emails, but it’s not stable. In other words, folders are better supported for searching than labels.

What’s more, bulk operations, including applying filters and bulk deletion, are slow and confusing.