Good news, finally I found what caused the search icon and the ‘Enter’ key not working! And it’s not connected to your plugin at all.
The programmer guy who started the construction of the site put a javascript file in the child theme with a tiny function disabling the search button:

` $(‘button.is-search-submit’).on(‘click’,function(e){
e.preventDefault();
}); `

I have no idea why he did it… I commented out the script and since then everything is working fine.
This is what happens if somebody starts something and somebody else need to finish. It took a lot of time to find this hidden little script grrrr…

So the plugin is working great, it was not your fault!
Sorry that I bothered you with this issue, and big thanks for your time spent with trying to help me.

Thank you!
A happy customer 🙂