Not sure how or when this happened, but my hierarchy editor has disappeared. I can access and move it normally when in the material room, but no matter where I move it to it disappears when I return to the pose room. It seems to be behind the main window somehow. In the image you can see a blur in the middle of my taskbar that disappears when the editor window is closed. Launching to factory settings doesn't seem to help, nor does switching to windowed vs. full screen. Anyone run into this one before?

I've never lost my hierarchy behind the taskbar, but I've lost my library. When you say launching to factory settings, are you looking in the interface tab rather than the documents tab of the General preferences? There are two settings with very similar names so it's easy to look at the wrong one. Also, I see you have 2 UI dots set. Have you tried clicking on one of those? Unless you created them since you started having this problem, either of those should get it to a different location.

Thank you so much, the UI dot did bring it back!

Lucky that the dot widget had "UI" selected  instead of "Pose" or "Camera" which I use much more frequently. Come to think of it, I don't remember even setting those dots...

If it is just behind the taskbar, go into your Windows settings and under Taskbar, click on the 'Automatically hide the taskbar in desktop mode'.  That action will hide the Taskbar down giving you access to the panel.