FeedHarbor Briefing Deck by John Parker

The extension lets users add RSS or Atom feeds, refresh them manually or on a schedule, read new items in one place, star useful stories, filter by status, search titles and feed names, export the subscription list as OPML, import OPML outlines, and copy a Markdown briefing of visible items. A background monitor updates feeds periodically, displays a toolbar unread badge, and can show a Firefox notification when new feed entries arrive.