diff --git a/scripts/prepareServiceWorker.ts b/scripts/prepareServiceWorker.ts
new file mode 100644
index 000000000..71f3ebbc7
--- /dev/null
+++ b/scripts/prepareServiceWorker.ts
@@ -0,0 +1,21 @@
+import Script from "./Script"
+import Constants from "../src/Models/Constants"
+import { writeFileSync } from "fs"
+
+class PrepareServiceWorker extends Script {
+    constructor() {
+        super("Super various little jobs to help the service worker")
+
+    }
+
+    public async main() {
+        const v = Constants.vNumber
+        writeFileSync("./src/service-worker/SWGenerated.ts",
+            ["export class SWGenerated {",
+                "// generated by scripts/prepareServiceWorker.ts",
+                "static vNumber = " + JSON.stringify(v), "}"].join("\n")
+            , "utf8")
+    }
+}
+
+new PrepareServiceWorker().run()
diff --git a/src/Logic/Web/IsOnline.ts b/src/Logic/Web/IsOnline.ts
new file mode 100644
index 000000000..9764c177d
--- /dev/null
+++ b/src/Logic/Web/IsOnline.ts
@@ -0,0 +1,19 @@
+import { Store, UIEventSource } from "../UIEventSource"
+
+export class IsOnline {
+    private static readonly _isOnline: UIEventSource<boolean> = new UIEventSource(navigator.onLine)
+    static {
+
+        window.addEventListener("online", () => {
+            IsOnline._isOnline.set(true)
+        })
+
+        window.addEventListener("offline", () => {
+            IsOnline._isOnline.set(false)
+
+        })
+    }
+
+    public static readonly isOnline: Store<boolean> = IsOnline._isOnline
+
+}
diff --git a/src/service-worker/SWGenerated.ts b/src/service-worker/SWGenerated.ts
new file mode 100644
index 000000000..23483a4c5
--- /dev/null
+++ b/src/service-worker/SWGenerated.ts
@@ -0,0 +1,4 @@
+export class SWGenerated {
+// generated by scripts/prepareServiceWorker.ts
+static vNumber = "0.54.4"
+}
\ No newline at end of file