MailTags for Mindspring?

I am new to Mindspring, and so far like it very much.

I was using a plug-in with Mac Mail, called Small Cubed Mail Suite. Mostly I was using it because of “Mail Tags” which allowed me to “Tag” an email and search for it by tag designation.

Is there such a resource on Mindspring, where I can create “Tags” for my emails. Or is there a way to install Small Cubed Mail Suite on Mindspring?