diff --git a/demos/vue/ckeditor5/src/App.vue b/demos/vue/ckeditor5/src/App.vue
index 08dc54c5a..ecc92e175 100644
--- a/demos/vue/ckeditor5/src/App.vue
+++ b/demos/vue/ckeditor5/src/App.vue
@@ -32,6 +32,7 @@ const content = Generic.editorContentMathML;
 const toolbar = ["bold", "italic", "link", "undo", "redo", "MathType", "ChemType", "sourceEditing"];
 const plugins = [Essentials, Bold, Italic, Link, Paragraph, MathType, SourceEditing];
 const editorConfig = {
+  licenseKey: 'GPL',
   iframe: true,
   charCounterCount: false,
   plugins,