diff --git a/package.json b/package.json
index f32b319..d2891a1 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "turn-off-the-lights-browser-extension",
-  "version": "4.5.2",
+  "version": "4.5.3",
   "description": "Browser extension",
   "homepage": "https://wwww.turnoffthelights.com",
   "author": "Stefan Van Damme",
diff --git a/src/manifests/safari.json b/src/manifests/safari.json
index 9c6b8d6..5eb4327 100644
--- a/src/manifests/safari.json
+++ b/src/manifests/safari.json
@@ -10,7 +10,7 @@
     }
   },
   "background": {
-    "service_worker": "scripts/background.js",
+    "scripts": ["scripts/constants.js", "scripts/background.js"],
     "persistent": false
   },
   "commands": {
diff --git a/src/scripts/background.js b/src/scripts/background.js
index 8e946a8..c0e5936 100755
--- a/src/scripts/background.js
+++ b/src/scripts/background.js
@@ -28,8 +28,13 @@ To view a copy of this license, visit http://creativecommons.org/licenses/GPL/2.
 //================================================
 
 // Importing the constants
-// eslint-disable-next-line no-undef
-importScripts("constants.js");
+// Check if the browser supports service workers
+// Safari uses a background script because iOS service workers are quickly terminated
+if(typeof importScripts === "function"){
+	// Importing the constants only if importScripts is available
+	// eslint-disable-next-line no-undef
+	importScripts("constants.js");
+}
 
 chrome.runtime.onMessage.addListener(function request(request, sender){
 	// eye protection & autodim & shortcut
diff --git a/xcode/Turn-Off-the-Lights-Safari-extension/Config.xcconfig b/xcode/Turn-Off-the-Lights-Safari-extension/Config.xcconfig
index 1726e20..f0f5847 100644
--- a/xcode/Turn-Off-the-Lights-Safari-extension/Config.xcconfig
+++ b/xcode/Turn-Off-the-Lights-Safari-extension/Config.xcconfig
@@ -9,5 +9,5 @@
 // https://help.apple.com/xcode/#/dev745c5c974
 
 // Update the version number here for all platforms
-VERSION = 4.5.2
-BUILD_NUMBER = 132
+VERSION = 4.5.3
+BUILD_NUMBER = 133
diff --git a/xcode/Turn-Off-the-Lights-Safari-extension/Turn Off the Lights for Safari.xcodeproj/project.xcworkspace/xcuserdata/stefanvandamme.xcuserdatad/UserInterfaceState.xcuserstate b/xcode/Turn-Off-the-Lights-Safari-extension/Turn Off the Lights for Safari.xcodeproj/project.xcworkspace/xcuserdata/stefanvandamme.xcuserdatad/UserInterfaceState.xcuserstate
index 427eed2..0b9eecc 100644
Binary files a/xcode/Turn-Off-the-Lights-Safari-extension/Turn Off the Lights for Safari.xcodeproj/project.xcworkspace/xcuserdata/stefanvandamme.xcuserdatad/UserInterfaceState.xcuserstate and b/xcode/Turn-Off-the-Lights-Safari-extension/Turn Off the Lights for Safari.xcodeproj/project.xcworkspace/xcuserdata/stefanvandamme.xcuserdatad/UserInterfaceState.xcuserstate differ