Currently Proton Mail strips the text/plain content from the body of a mixed content email (e.g. email with both text/plain and text/html). Proton Mail should preserve the entire message body intact. Besides the uneasy feeling I get knowing that email messages are parsed and stripped of content, stripping the text/plain part forces us to view the HTML version of an email which is undesirable from a security/privacy standpoint, not to mention my general distaste for HTML in email. In any case, email message content should not be parsed/stripped (inspected?) and users should be able to configure any email client to view email messages with either text/plain or text/html by default.