diff --git a/ext/bg/js/search.js b/ext/bg/js/search.js
index 88be335f..e968e8cf 100644
--- a/ext/bg/js/search.js
+++ b/ext/bg/js/search.js
@@ -438,7 +438,7 @@ class DisplaySearch extends Display {
         const {frameId} = await api.frameInformationGet();
 
         const popupFactory = new PopupFactory(frameId);
-        await popupFactory.prepare();
+        popupFactory.prepare();
 
         const frontend = new Frontend(
             frameId,
diff --git a/ext/bg/js/settings/popup-preview-frame-main.js b/ext/bg/js/settings/popup-preview-frame-main.js
index 4c6096ec..866b9f57 100644
--- a/ext/bg/js/settings/popup-preview-frame-main.js
+++ b/ext/bg/js/settings/popup-preview-frame-main.js
@@ -28,7 +28,7 @@
         const {frameId} = await api.frameInformationGet();
 
         const popupFactory = new PopupFactory(frameId);
-        await popupFactory.prepare();
+        popupFactory.prepare();
 
         const preview = new PopupPreviewFrame(frameId, popupFactory);
         await preview.prepare();
diff --git a/ext/fg/js/content-script-main.js b/ext/fg/js/content-script-main.js
index c4aa1bca..1f3a69e5 100644
--- a/ext/fg/js/content-script-main.js
+++ b/ext/fg/js/content-script-main.js
@@ -32,7 +32,7 @@
         }
 
         const popupFactory = new PopupFactory(frameId);
-        await popupFactory.prepare();
+        popupFactory.prepare();
 
         const frontend = new Frontend(
             frameId,
diff --git a/ext/fg/js/float.js b/ext/fg/js/float.js
index 199990e5..d7beb675 100644
--- a/ext/fg/js/float.js
+++ b/ext/fg/js/float.js
@@ -241,7 +241,7 @@ class DisplayFloat extends Display {
         const {frameId} = await api.frameInformationGet();
 
         const popupFactory = new PopupFactory(frameId);
-        await popupFactory.prepare();
+        popupFactory.prepare();
 
         const frontend = new Frontend(
             frameId,
diff --git a/ext/fg/js/popup-factory.js b/ext/fg/js/popup-factory.js
index 4edda91f..904f18b9 100644
--- a/ext/fg/js/popup-factory.js
+++ b/ext/fg/js/popup-factory.js
@@ -28,7 +28,7 @@ class PopupFactory {
 
     // Public functions
 
-    async prepare() {
+    prepare() {
         api.crossFrame.registerHandlers([
             ['getOrCreatePopup',   {async: false, handler: this._onApiGetOrCreatePopup.bind(this)}],
             ['setOptionsContext',  {async: true,  handler: this._onApiSetOptionsContext.bind(this)}],