I would love FastMail to add tags or labels. That is the one primary feature making me still forward my FastMail email to Gmail. I love having email in my inbox already labeled (or tagged) so I can have context.
For example, one of the companies I work for uses purple in their logo. So I tag all emails from them with their company name, and add make it purple.
For example, one of the companies I work for uses purple in their logo. So I tag all emails from them with their company name, and add make it purple.