Fix CORS proxy

Author: niutech

htmlpreview.js

@@ -88,13 +88,11 @@
 
 	var fetchProxy = function (url, options, i) {
 		var proxy = [
-			//'https://cors.io/?',
-			'https://jsonp.afeld.me/?url=',
+			'https://thingproxy.freeboard.io/fetch/',
+			'https://yacdn.org/serve/',
 			'https://cors-anywhere.herokuapp.com/'
 		];
 		return fetch(proxy[i] + url, options).then(function (res) {
-			if (!res.ok)
-				throw new Error('Cannot load ' + url + ': ' + res.status + ' ' + res.statusText);
 			return res.text();
 		}).catch(function (error) {
 			if (i === proxy.length - 1)
@@ -104,7 +102,10 @@
 	};
 
 	if (url && url.indexOf(location.hostname) < 0)
-		fetchProxy(url, null, 0).then(loadHTML).catch(function (error) {
+		fetch(url).then(function (res) {
+			if (!res.ok) throw new Error('Cannot load ' + url + ': ' + res.status + ' ' + res.statusText);
+			return res.text();
+		}).then(loadHTML).catch(function (error) {
 			console.error(error);
 			previewForm.style.display = 'block';
 			previewForm.innerText = error;