There is one footgun with many tools like this. If you add a new source to an existing combined feed all of the items in that feed will immediately appear as ne

There is one footgun with many tools like this. If you add a new source to an existing combined feed all of the items in that feed will immediately appear as new items. What you typically want is for new items for the source feed to show up in the combined feed, not all exiting items at once.