Donald105,
Thanks for your suggestion. I gave your recommendation a try by attempting to add the functionality of disabling the extension by url using the Extension Automation extension to Chrome. I confirmed that I had a properly applied filter to disable Avast Passwords for the Wordpress site I was working on. But it had no effect. The Avast Passwords Extension still seemed to be enabled for the site, and disabling it all together was (as has been the case) the only way to get the menus page functioning again.
Is this forum only a "users helping users" situation? Is there somewhere else I should be making a bug report? If my assumption is correct: that this will effect all Wordpress installations, then we're talking about 30% of all websites world wide. Seems like fixing this bug might be important?
Nevertheless, your suggestions are appreciated. Thank you.