I see it. I’ve clicked on it. But I can’t figure out what it does.
aha. I can see (somewhat) how that’s nice.
Now fondly known as the Dorito - https://getsatisfaction.com/newsblur/…
Thanks for the answer!
Watch the left side of the story pane and move your mouse around. See that little orange arrow moving around? It is following your mouse. A story is marked as read when the arrow hits the title of a story. “Lock” makes the arrow stay in place instead of following your mouse.