Replace textarea.value calls

assets/editor/movie.js

@@ -49,22 +49,28 @@ window.EditorMovie = (function () {
         return out.join('\n');
     }
 
+    function replaceRange(ta, start, end, text) {
+        ta.focus();
+        ta.selectionStart = start;
+        ta.selectionEnd = end;
+        document.execCommand('insertText', false, text);
+    }
+
     function insertOrReplace(ta, markup) {
         var t = ta.value || '';
         var b = t.indexOf(BEGIN);
         var e = t.indexOf(END);
         if (b !== -1 && e !== -1 && e > b) {
-            ta.value = t.slice(0, b) + markup + t.slice(e + END.length);
+            replaceRange(ta, b, e + END.length, markup);
         } else {
             var h = t.match(/^#{1,6}\s+.+?\s*$/m);
             if (h) {
                 var idx = t.indexOf(h[0]) + h[0].length;
-                ta.value = t.slice(0, idx) + '\n\n' + markup + t.slice(idx);
+                replaceRange(ta, idx, idx, '\n\n' + markup);
             } else {
-                ta.value = markup + (t ? '\n\n' + t : '');
+                replaceRange(ta, 0, 0, t ? markup + '\n\n' : markup);
             }
         }
-        ta.dispatchEvent(new Event('input'));
     }
 
     function fetchMovie(title, year) {