Just set a custom tag to your new bookmarks and Inoreader will do its best to find the underlying RSS feed behind it and subscribe you to it.
If
New public bookmark tagged
This Trigger fires every time you create a new public bookmark with a single tag you specify. NOTE: excludes bookmarks marked to read later.
Then
Subscribe to feed
This Action will try to find an RSS feed from the provided URL and subscribe you to it.
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