auto-apply settings when extension installed

static/app.js

@@ -300,11 +300,17 @@ function showTools() {
     if (slowInterval) clearInterval(slowInterval), slowInterval = null;
   }
 
+  function applySettings() {
+    window.postMessage({ kind: "snotes-settings", serverUrl: window.location.origin }, "*");
+  }
+
   function onDetected() {
+    const wasDetected = detected;
     detected = true;
     stopPing();
     extStatus.textContent = "✓ Extension detected";
     installBtn.textContent = "Extension installed";
+    if (!wasDetected) setTimeout(applySettings, 300);
   }
 
   function doPing() {
@@ -330,7 +336,7 @@ function showTools() {
   });
 
   qsApply.addEventListener("click", () => {
-    window.postMessage({ kind: "snotes-settings", serverUrl: window.location.origin }, "*");
+    applySettings();
     qsStatus.textContent = "Applying…";
     setTimeout(() => { if (qsStatus.textContent === "Applying…") qsStatus.textContent = "No response — is the extension installed?"; }, 5000);
   });