A quick and simple way to limit the amount of time a gh-pages prototype can be viewed.

temp_access_to_ghpages.js

(function( doc, dNow ){
	var bOk = false;
	var urlParams = new URLSearchParams( window.location.search );
	if( urlParams.has( "token" ) ){
		var sToken = urlParams.get( "token" );
		var nDiff = ( dNow.getTime() - Number( sToken ) ) / 1000;
		if( nDiff >= 3000 || isNaN( nDiff ) ){
			bOk = false;
		}else{
			bOk = true;
		}
	}
	if( !bOk ){
		document.body.style.display = "none";
		alert("Token Timeout, Please request a new token.");		
	}
})( document, new Date() );
//  Type this into console var dX = new Date();console.log( dX.getTime() );
//  Send link with the following at the end ?token=number from above.