Dewey, perhaps a dumb suggestion but have you tried to add the website to the compatibility list within IE11 ?
I was finding many website with buttons (nothing to do with Avast) to not work in IE11 which they did work fine is IE10 or before.
I tried Firefox and no problem.
Stumbled on the “compatibility” whitelist…just go to IE11>Settings>Compatibility View Settings.
While you are at the offending website just add to list, restart IE11, try again.

Not sure this is your issue but thought I’d throw out the suggestion.