diff --git a/src/common/feature-detect/support-web-components.ts b/src/common/feature-detect/support-web-components.ts
new file mode 100644
index 0000000000..607b3713ca
--- /dev/null
+++ b/src/common/feature-detect/support-web-components.ts
@@ -0,0 +1,2 @@
+export const webComponentsSupported =
+  "customElements" in window && "content" in document.createElement("template");
diff --git a/src/entrypoints/custom-panel.ts b/src/entrypoints/custom-panel.ts
index d6f0a33d74..9e14dc52c1 100644
--- a/src/entrypoints/custom-panel.ts
+++ b/src/entrypoints/custom-panel.ts
@@ -5,6 +5,7 @@ import { setCustomPanelProperties } from "../util/custom-panel/set-custom-panel-
 import { fireEvent } from "../common/dom/fire_event";
 import { PolymerElement } from "@polymer/polymer";
 import { CustomPanelInfo } from "../data/panel_custom";
+import { webComponentsSupported } from "../common/feature-detect/support-web-components";
 
 declare global {
   interface Window {
@@ -12,18 +13,13 @@ declare global {
   }
 }
 
-const webComponentsSupported =
-  "customElements" in window &&
-  "import" in document.createElement("link") &&
-  "content" in document.createElement("template");
-
 let es5Loaded: Promise<unknown> | undefined;
 
 window.loadES5Adapter = () => {
   if (!es5Loaded) {
     es5Loaded = Promise.all([
       loadJS(
-        `${__STATIC_PATH__}/polyfills/custom-elements-es5-adapter.js`
+        `${__STATIC_PATH__}polyfills/custom-elements-es5-adapter.js`
       ).catch(),
       import(/* webpackChunkName: "compat" */ "./compatibility"),
     ]);
@@ -50,7 +46,7 @@ function initialize(panel: CustomPanelInfo, properties: {}) {
 
   if (!webComponentsSupported) {
     start = start.then(() =>
-      loadJS(`${__STATIC_PATH__}/polyfills/webcomponents-bundle.js`)
+      loadJS(`${__STATIC_PATH__}polyfills/webcomponents-bundle.js`)
     );
   }