Finder sidebar missing all of a sudden

Hey all. Starting today, my sidebar in the finder windows is gone. All the Finder preferences are still checked, but under the Finder/view menu, "Show Sidebar" is greyed out. I have rebooted the Mac and relaunched the finder several times to no avail.

Upgraded to Catalina 2 weeks ago and has been working fine until now.

no new software has been installed anytime recently.

There's basically no way to get to any local folder other than Documents.