Frameless Output Issues

I created a frameless output using a customized copy of the Orange skin and RoboHelp 2020.4.173.  We have Windows 2019 running on our server.  The output displays and functions correctly for me when I use Chrome, the Chromium version of Edge, or Firefox.  It does not work using IE, Safari, or Opera.  Is this expected?

A customer reported that the Search is not working using Chrome or Edge (and to my knowledge did not try Firefox).  When the customer enters data in the search field, the system displays a drop-down list of matching search terms.  If the customer clicks one of the search terms or clicks Enter, nothing happens.  Is anyone else experiencing this?  Ideas on how to resolve? Would there be any security and/or browser settings that would allow the Search to work for some individuals and not for others?

Thanks!