diff --git a/backend/extension-src/content-script.js b/backend/extension-src/content-script.js
index f322596..bde89ed 100644
--- a/backend/extension-src/content-script.js
+++ b/backend/extension-src/content-script.js
@@ -358,6 +358,13 @@ function buildTabletBanner(bookingId) {
 }
 
 function processCheckinPageBanner() {
+  // bookings_view has its own `ui-tabs-nav` tablist too (Mandatory
+  // Information / Optional Booking Details / Newbook Drive) — without this
+  // guard this banner duplicated there alongside processCheckinBanner's
+  // augmented reminder banner (confirmed 2026-10-01 from a live screenshot).
+  // This one is purely for the dedicated bookings_checkin/<id> page.
+  if (!/^\/bookings_checkin\//.test(location.pathname)) return;
+
   const tablist = document.querySelector('ul[role="tablist"].ui-tabs-nav');
   if (!tablist || tablist.hasAttribute(PROCESSED_ATTR)) return;
   const bookingId = extractBookingIdFromLocation();
diff --git a/backend/extension-src/options/options.js b/backend/extension-src/options/options.js
index 8aea603..5525aa3 100644
--- a/backend/extension-src/options/options.js
+++ b/backend/extension-src/options/options.js
@@ -40,8 +40,19 @@ async function refreshDeviceList(preselectId) {
     defaultDeviceSelect.innerHTML = devices.map(d =>
       `<option value="${d.device_id}">${escapeHtml(d.name)}</option>`
     ).join('');
-    if (preselectId) defaultDeviceSelect.value = preselectId;
+    if (preselectId && devices.some(d => d.device_id === preselectId)) {
+      defaultDeviceSelect.value = preselectId;
+    }
     defaultSection.style.display = '';
+    // A <select> always shows *something* selected — the browser defaults to
+    // the first <option> with no explicit selection, with no 'change' event
+    // firing for that. Without this, a machine with only one tablet (or
+    // whoever's happy with the first one) never actually got a default
+    // saved, despite the dropdown visibly showing one selected — the
+    // injected buttons would then always fall back to the manual picker
+    // (confirmed live 2026-10-01). Persisting whatever ends up selected here
+    // keeps storage and the visible dropdown state from ever drifting apart.
+    chrome.storage.local.set({ defaultDeviceId: defaultDeviceSelect.value });
   } catch {
     // Not configured/reachable yet — leave the section hidden rather than
     // showing an empty/broken picker; Test Connection surfaces the real error.
@@ -83,7 +94,8 @@ async function save() {
   await chrome.storage.local.set({ baseUrl, apiKey });
   statusEl.textContent = 'Saved.';
   statusEl.style.color = '#16a34a';
-  refreshDeviceList();
+  const { defaultDeviceId } = await chrome.storage.local.get('defaultDeviceId');
+  refreshDeviceList(defaultDeviceId);
 }
 
 async function test() {
@@ -93,7 +105,8 @@ async function test() {
     const devices = await fetchDevices();
     statusEl.textContent = `Connected — found ${devices.length} tablet(s).`;
     statusEl.style.color = '#16a34a';
-    refreshDeviceList();
+    const { defaultDeviceId } = await chrome.storage.local.get('defaultDeviceId');
+    refreshDeviceList(defaultDeviceId);
   } catch (err) {
     statusEl.textContent = `Failed: ${err.message}`;
     statusEl.style.color = '#dc2626';