I guess that I'll have to wait until the next time that updates are available to see if App Store is behaving. For no reason that I can discern, App Store is now normal. I can see updates installed in the last 30 days and was notified of an update to iMovie.
Jon
macOS 11.7.10, iMac Retina 5K 27-inch, late 2014, 3.5 GHz Intel Core i5, 1 TB fusion drive, 16 GB RAM, Epson SureColor P600, Photoshop CC, Lightroom CC, MS Office 365
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