Please, add pin number to email's subject. Where we have email client or email's website (like gmail website) with active thread view (grouping emails with the same subject) then we have one long mail with many different pins with one subtect, for example: [project name] Replied to your comment in Toybox! So can't work efficiently. Email notyfications should be regardless of whether it is a notification about a new comment, mention, change of assignment, etc. For example, if there are new comments in a specific pin number 222 on toybox, the email notyfication title should contain pin number, i.e: [project name] [222] Replied to your comment in Toybox!

And accordingly for other types of notifications

Best!

Michal