diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1520755..fa5224b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,12 @@ All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](http://keepachangelog.com/) and this project adheres to [Semantic Versioning](http://semver.org/).
 
+## v1.4.3
+
+Fixed
+
+- Failed to get the process key during custom application initialization
+
 ## v1.4.2
 
 - Support for payment methods `in3`, `alma`, `payconiq`
diff --git a/application/custom-application-config.ts b/application/custom-application-config.ts
index 5a8d35f..d6c8751 100644
--- a/application/custom-application-config.ts
+++ b/application/custom-application-config.ts
@@ -32,11 +32,6 @@ const config = {
     labelAllLocales: [],
     permissions: [PERMISSIONS.Manage],
   },
-  headers: {
-    csp: {
-      'connect-src': ['*.euope-west1.gcp.commercetoolsr.app'],
-    },
-  },
 };
 
 export default config;
diff --git a/application/package.json b/application/package.json
index d7bc7fc..5e497c4 100644
--- a/application/package.json
+++ b/application/package.json
@@ -1,6 +1,6 @@
 {
   "name": "shopmacher-mollie-application",
-  "version": "1.4.2",
+  "version": "1.4.3",
   "description": "Integration application between commercetools and mollie payment service provider",
   "private": true,
   "scripts": {
diff --git a/application/src/constants.ts b/application/src/constants.ts
index 70b0581..360a2c2 100644
--- a/application/src/constants.ts
+++ b/application/src/constants.ts
@@ -1,19 +1,39 @@
 // Make sure to import the helper functions from the `ssr` entry point.
 import { entryPointUriPathToPermissionKeys } from '@commercetools-frontend/application-shell/ssr';
 
-export const entryPointUriPath = process.env.ENTRY_POINT_URI_PATH ?? 'mollie';
+declare global {
+  interface Window {
+    app?: {
+      [key: string]: string;
+      entryPointUriPath: string;
+    };
+  }
+}
+
+const getConfig = (processKey: string, windowKey: string) => {
+  return typeof window === 'undefined'
+    ? process.env[processKey]
+    : window.app?.[windowKey];
+};
+
+export const entryPointUriPath =
+  getConfig('ENTRY_POINT_URI_PATH', 'entryPointUriPath') ?? 'mollie';
+
 export const PERMISSIONS = entryPointUriPathToPermissionKeys(entryPointUriPath);
-export const CLOUD_IDENTIFIER = process.env.CLOUD_IDENTIFIER ?? 'gcp-eu';
-export const CUSTOM_APPLICATION_ID = process.env.CUSTOM_APPLICATION_ID ?? '';
+export const CLOUD_IDENTIFIER =
+  getConfig('CLOUD_IDENTIFIER', 'cloudIdentifier') ?? 'gcp-eu';
+export const CUSTOM_APPLICATION_ID =
+  getConfig('CUSTOM_APPLICATION_ID', 'customApplicationId') ?? '';
 export const APPLICATION_URL =
-  process.env.APPLICATION_URL ?? 'https://mollie.app';
+  getConfig('APPLICATION_URL', 'applicationUrl') ?? 'https://your-app-url.com';
+
 export const OBJECT_CONTAINER_NAME = 'sctm-app-methods';
 export const EXTENSION_KEY = 'sctm-payment-create-update-extension';
 export const EXTENSION_URL_PATH = '/processor';
 export const APPLICATION_URL_PATH = '/application/methods';
 export const USER_AGENT = {
-  name: 'ShopmacherMollieCommercetoolsConnector/1.4.2',
-  version: '1.4.2',
-  libraryName: 'ShopmacherMollieCommercetoolsConnector/1.4.2',
+  name: 'ShopmacherMollieCommercetoolsConnector/1.4.3',
+  version: '1.4.3',
+  libraryName: 'ShopmacherMollieCommercetoolsConnector/1.4.3',
   contactEmail: 'info@mollie.com',
 };
diff --git a/processor/package-lock.json b/processor/package-lock.json
index f11a8cf..9b0e424 100644
--- a/processor/package-lock.json
+++ b/processor/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "shopmacher-mollie-processor",
-  "version": "1.4.2",
+  "version": "1.4.3",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "shopmacher-mollie-processor",
-      "version": "1.4.2",
+      "version": "1.4.3",
       "hasInstallScript": true,
       "license": "MIT",
       "dependencies": {
@@ -9325,4 +9325,4 @@
       }
     }
   }
-}
\ No newline at end of file
+}
diff --git a/processor/package.json b/processor/package.json
index 024bde8..2001242 100644
--- a/processor/package.json
+++ b/processor/package.json
@@ -1,7 +1,7 @@
 {
   "name": "shopmacher-mollie-processor",
   "description": "Integration between commercetools and mollie payment service provider",
-  "version": "1.4.2",
+  "version": "1.4.3",
   "main": "index.js",
   "private": true,
   "scripts": {