159.0 - Calendar is blanked post-update, & my Advanced Settings screens don't match what's described in the support article here.

My Thunderbird installation (159.0/Windows11) has evidently just updated, and my Calendar tab is suddenly a complete blank space. There's a support article here that appears to discuss exactly this situation, and gives precise steps for getting into "Config Editor" in Advanced Settings, entering a long search string, and issuing a Reset command. (Mail and contacts are just fine.) Which I tried... But there is no "Config Editor" button in the dialog I get when clicking Advanced Settings at the bottom of the Settings tab, only a mostly blank screen with no list of settings and a dialog box in which one can enter text (with options for "Boolean", "Number" and "String"). And entering the search string given in the support article produces, with a bit of finagling, a toggle that will change its setting from True to False and back again (and a trash-bin icon that offers to delete it), but neither "True" nor "False" produces any instance of a "Lightning" extension in my list of extensions (which is short and uncomplicated), so (a) I can't delete the extension as instructed, because it's not there, and (b) restarting Thunderbird only continues to give me the unhelpfully blank Calendar tab. (And I do mean "blank" here - there isn't even an empty calendar grid on that tab at this point.) I *think* the article is probably right that my data is still there (I can see .ics files with current dates in File Explorer), but at this point I can't get at it and can't seem to get the interface unstuck.