Fix bug crashing the page when adding <script> tag only in the post editor

src/app/components/cards/MarkdownViewer.jsx

@@ -123,7 +123,10 @@ class MarkdownViewer extends Component {
         }
 
         // Needs to be done here so that the tags added by HighlightJS won't be filtered of by the sanitizer
-        cleanText = highlightCodes(cleanText).html;
+        const higlightedText = highlightCodes(cleanText).html;
+        if (higlightedText) {
+            cleanText = higlightedText;
+        }
 
         const noImageActive = cleanText.indexOf(noImageText) !== -1;
 

src/shared/HtmlReady.js

@@ -146,10 +146,16 @@ function traverseForCodeHighlight(node, depth = 0) {
 }
 
 export function highlightCodes(html) {
-    const doc = DOMParser.parseFromString(html, 'text/html');
-    traverseForCodeHighlight(doc);
+    if (html.match(/<code>.*?<\/code>/s)) {
+        const doc = DOMParser.parseFromString(html, 'text/html');
+        traverseForCodeHighlight(doc);
+        return {
+            html: doc ? XMLSerializer.serializeToString(doc) : '',
+        };
+    }
+
     return {
-        html: doc ? XMLSerializer.serializeToString(doc) : '',
+        html: null,
     };
 }