link calendar entry to an email

In previous versions of OSX it was possible to link a calendar entry to an email, just by dragging that email and dropping it onto the calendar entry. This does not seem to work in Catalina, it just adds the "subject" of the email as a hyperlink but when clicking on this hyperlink, it opens safari to an empty page rather than opening email onto the right email.

This is a big problem for me because I often have meetings that have to do with specific emails and it was useful to quickly get back to the email by clicking on a hyperlink.

has anyone encountered this issue and found a workaround?

thanks for your thoughts