diff --git a/js/pacosako_ui.js b/js/pacosako_ui.js
index 32d8f4a..a1c2908 100644
--- a/js/pacosako_ui.js
+++ b/js/pacosako_ui.js
@@ -786,30 +786,40 @@ $(function (){
 
       Promise.resolve().then(async () => {
          const wb = new Workbox('sw.js');
+         let latest_sw = null;
 
          function showSkipWaitingPrompt(event) {
-            if (confirmBox) {
-               confirmBox.close({ ignoreDelay: true });
+            latest_sw = event.sw;
+
+            if (!confirmBox) {
+               confirmBox = new jBox('Confirm', {
+                  attach: null,
+                  content: "A new version is available. Update the page?",
+                  confirmButton: `<span class="update-confirm-button">Update</span>`,
+                  cancelButton: 'Not now',
+                  closeOnConfirm: false,
+                  async confirm() {
+                     /* The SW should signal us to reload, but do it after 20s regardless. */
+                     setTimeout(() => { window.location.reload(); }, 20000);
+                     messageSW(latest_sw, {type: 'SKIP_WAITING'});
+                     $('.update-confirm-button').text('Updating…');
+                  },
+                  onClose() {
+                     if (confirmBox === this) {
+                        confirmBox = null;
+                     }
+                  },
+                  onCloseComplete() {
+                     this.destroy();
+                  },
+               });
+
+               confirmBox.open();
             }
+         }
 
-            confirmBox = new jBox('Confirm', {
-               attach: null,
-               content: "A new version is available. Update the page?",
-               confirmButton: `<span class="update-confirm-button">Update</span>`,
-               cancelButton: 'Not now',
-               closeOnConfirm: false,
-               confirm() {
-                  /* The SW should signal us to reload, but do it after 20s regardless. */
-                  setTimeout(() => { window.location.reload(); }, 20000);
-                  messageSW(event.sw, {type: 'SKIP_WAITING'});
-                  $('.update-confirm-button').text('Updating…');
-               },
-               onCloseComplete() {
-                  this.destroy();
-               },
-            });
-
-            confirmBox.open();
+         function reloadForUpdate(event) {
+            window.location.reload();
          }
 
          wb.addEventListener('installed', (event) => {
@@ -822,23 +832,18 @@ $(function (){
             }
          });
 
-         wb.addEventListener('controlling', (event) => {
-            if (event.isUpdate) {
-               window.location.reload();
-            }
-         });
-
          wb.addEventListener('waiting', showSkipWaitingPrompt);
          wb.addEventListener('externalwaiting', showSkipWaitingPrompt);
 
+         wb.addEventListener('controlling', reloadForUpdate);
+         wb.addEventListener('externalactivated', reloadForUpdate);
+
          const registration = await wb.register();
 
-         if ('update' in registration) {
-            /* Check for updates every 4h without reloading the page. */
-            setInterval(() => { registration.update(); }, 4*3600*1000);
-         } else {
-            console.log('service worker update method not supported, disabling update checks');
-         }
+         /* Check for updates every 4h without reloading the page. */
+         setInterval(() => { wb.update(); }, 4*3600*1000);
+
+         window.Admin.workbox = wb;
       }).catch((err) => {
          console.error('failed to register the service worker', err);
          disableNotify();
diff --git a/sw.js b/sw.js
index 9303307..4b58a4a 100644
--- a/sw.js
+++ b/sw.js
@@ -14,3 +14,7 @@ addEventListener('message', (event) => {
       skipWaiting();
    }
 });
+
+self.addEventListener('activate', (event) => {
+   event.waitUntil(clients.claim());
+});