Fix preview command for tests

6 years ago · ccfc0b18f3
1 changed files with 2 additions and 1 deletions
--- a/src/commands/view/Preview.js
+++ b/src/commands/view/Preview.js
@ -22,8 +22,9 @@ export default {
  },

  tglEffects(on) {
+    const { em } = this;
    const mthEv = on ? 'on' : 'off';
-    this.em[mthEv]('run:tlb-move:before', this.preventDrag);
+    em && em[mthEv]('run:tlb-move:before', this.preventDrag);
  },

  run(editor, sender) {