Can somebody explain me how OPML works for RSS? Are these files usually imported into the RSS reader apps or are they used where they are? If I import multiple OPML files with multiple feeds, will the feeds from the first OPML be overwritten by those in the second one or will they add up? Will article read/unread status be synced to multiple devices if I use the same OPML file or not?
OPML files really aren’t much more than a list of the feeds you’re subscribed to. Individual posts or articles aren’t in there. I would expect that importing a second OPML file would just add more subscriptions, but it’d be up to the reader app to decide what it does.