diff --git a/app/assets/javascripts/wizard/components/theme-preview.js.es6 b/app/assets/javascripts/wizard/components/theme-preview.js.es6
index b268bab8167..768e2e5522b 100644
--- a/app/assets/javascripts/wizard/components/theme-preview.js.es6
+++ b/app/assets/javascripts/wizard/components/theme-preview.js.es6
@@ -6,7 +6,6 @@ import {
   chooseDarker,
   LOREM
 } from "wizard/lib/preview";
-import { computed } from "@ember/object";
 
 export default createPreviewComponent(305, 165, {
   logo: null,
@@ -14,10 +13,6 @@ export default createPreviewComponent(305, 165, {
 
   classNameBindings: ["isSelected"],
 
-  canvasStyle: computed("width", "height", function() {
-    return `width:${this.width}px;height:${this.height}px`.htmlSafe();
-  }),
-
   @discourseComputed("selectedId", "colorsId")
   isSelected(selectedId, colorsId) {
     return selectedId === colorsId;
diff --git a/app/assets/javascripts/wizard/lib/preview.js.es6 b/app/assets/javascripts/wizard/lib/preview.js.es6
index 3f4d9fdf105..0ad6909f266 100644
--- a/app/assets/javascripts/wizard/lib/preview.js.es6
+++ b/app/assets/javascripts/wizard/lib/preview.js.es6
@@ -41,6 +41,7 @@ export function createPreviewComponent(width, height, obj) {
       height,
       elementWidth: width * scale,
       elementHeight: height * scale,
+      canvasStyle: `width:${width}px;height:${height}px`,
       ctx: null,
       loaded: false,