Most modern browsers and devices will not be able to use web technologies such as configuration websites, or status updates using Socket.IO, or WebRTC without a valid TLS certificate in place.
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Now you can double-click on your local certificate and see it is now trusted by your computer:
Be very careful with your certificates. By installing as a Trusted Root all certificates signed by those files will be treated as real and trustworthy by any machines that have your Trusted Root and password.