Is it possible to open an email message on OS X from within FileMaker using a message URL (e.g., message://<email message id>)? Folders, files, and websites can be opened using the "Open URL" script step, but when I enter a valid Message URL I get an error. Pasting the same URL into Safari correctly opens the referenced email message.
Is working with another applications URL scheme limited to FM GO on iOS?
A email have a internal ID. For that you first need to get that ID. For that you need a plugin in FileMaker.
There are several different plugins that works with emails
I have not seen anyone opening up a email within a Safari