I know I created a sketch and Extruded Cut to take the domed top off of this post, but why isn't it in the tree?  I've seen a lot of strange stuff, but this is a new one.  And before anyone asks, my computer was rebooted this morning, and I see the Rebuild symbol, but neither a regular rebuild or Ctrl+Q do anything.  I'm curious to see what happens when I save this Part, close it, and re-open.