Nope... FeedDemon is a stand-alone program (for Windows only, I suppose)
I almost always use the best standalone programs I can find, and FeedDemon is the best I have used, although even it has not been developed much lately.
It has options to "open in default browser" but that defeats MY purpose of having the simplest system possible that displays feeds as I want to see them.
By clicking on the User Name, you will requery the forum for that user. You will see everything that he or she has posted with that Mudcat name.
By clicking on the Thread Name, you will be sent to the Forum on that thread as if you selected it from the main Mudcat Forum page.
By clicking on the Subject, you will also go to the thread as if you selected it from the original Forum page, but also go directly to that particular message.
By clicking on the Date (Posted), you will dig out every message posted that day.
sj