This turned out to be a browser problem. The version of Chrome was 79 (kind of old).  I upgraded to Chrome 106 and the problem was resolved.

It's still a problem since we can't expect everyone to be using the latest browser. I've installed odoo 16 on ubuntu 22.04 server and when I access it in the chromium and mozilla browsers it give me a 

UncaughtClientError
Uncaught Javascript Error
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