diff --git a/internal/core/templates/add_repeater.html b/internal/core/templates/add_repeater.html
index c2b713f..d56a80c 100644
--- a/internal/core/templates/add_repeater.html
+++ b/internal/core/templates/add_repeater.html
@@ -143,7 +143,10 @@
 {{else if eq .Step "serial"}}
 {{/* ---- Step 3 (serial): configure a brand-new repeater and run over USB ---- */}}
 <div id="unsupported" class="alert alert-danger" role="alert" hidden>
-  This browser doesn't support the Web Serial API. Use Chrome, Edge, or another Chromium-based browser over HTTPS or on localhost.
+  <div>
+    This browser can't connect to USB devices. Use Chrome or Edge, or Firefox 151 or later,
+    on desktop — or Chrome on Android — over HTTPS or on localhost.
+  </div>
 </div>
 
 <div class="card">
@@ -279,6 +282,7 @@
 <link rel="stylesheet" href="{{ asset "/static/leaflet.css" }}">
 <script src="{{ asset "/static/leaflet.js" }}"></script>
 <script src="{{ asset "/static/regionmap.js" }}"></script>
+<script src="{{ asset "/static/serial-port.js" }}"></script>
 <script src="{{ asset "/static/serial-setup.js" }}"></script>
 
 {{else}}
diff --git a/internal/core/templates/console.html b/internal/core/templates/console.html
index bf1777a..edb0ab2 100644
--- a/internal/core/templates/console.html
+++ b/internal/core/templates/console.html
@@ -60,7 +60,10 @@ swap needs no new markup. The flex row is nested so the [hidden] attribute wins
       <div class="card-header"><h2 class="card-title">Console</h2></div>
       <div class="card-body">
         <div id="unsupported" class="alert alert-danger" role="alert" hidden>
-          This browser does not support WebSerial. Use Chrome, Edge, or another Chromium-based browser over HTTPS or on localhost.
+          <div>
+            This browser can't connect to USB devices. Use Chrome or Edge, or Firefox 151 or later,
+            on desktop — or Chrome on Android — over HTTPS or on localhost.
+          </div>
         </div>
         <div class="mb-3">
           <label class="form-label" for="path">Path <span class="form-label-description">optional</span></label>
@@ -154,5 +157,6 @@ swap needs no new markup. The flex row is nested so the [hidden] attribute wins
 <script nonce="{{.Nonce}}">
   window.MESHTENDER_WS = (location.protocol === "https:" ? "wss://" : "ws://") + location.host + "/repeaters/{{.Repeater.PublicID}}/console/ws{{if .Debug}}?debug=1{{end}}";
 </script>
+<script src="{{ asset "/static/serial-port.js" }}"></script>
 <script src="{{ asset "/static/console.js" }}"></script>
 {{end}}
diff --git a/internal/web/static/console.js b/internal/web/static/console.js
index 536be21..c35555d 100644
--- a/internal/web/static/console.js
+++ b/internal/web/static/console.js
@@ -6,7 +6,7 @@
 // separate "apply org configuration" script (console-config.js) can send commands
 // and react to session state without owning the socket:
 //   window.MeshConsole.ready          — is the modem connected & the session live?
-//   window.MeshConsole.supported       — does this browser have WebSerial at all?
+//   window.MeshConsole.supported       — can this browser reach a serial device at all?
 //   window.MeshConsole.connect()       — open the modem + session (needs a user gesture)
 //   window.MeshConsole.send(text)      — send a CLI command; returns false if not ready
 //   window.MeshConsole.getLocation()   — ask the server to fetch the repeater's coords
@@ -26,8 +26,8 @@
   // whether a command can be sent right now.
   const api = {
     ready: false,
-    supported: "serial" in navigator,
-    connect() {}, // replaced with the real routine below when WebSerial is present
+    supported: !!(window.MeshSerial && window.MeshSerial.supported),
+    connect() {}, // replaced with the real routine below when a serial transport is present
     send(text) {
       const t = String(text || "").trim();
       if (!t || !api.ready || !ws || ws.readyState !== WebSocket.OPEN) return false;
@@ -57,7 +57,7 @@
     return url;
   }
 
-  if (!("serial" in navigator)) {
+  if (!api.supported) {
     const unsupportedEl = document.getElementById("unsupported");
     if (unsupportedEl) unsupportedEl.hidden = false;
     if (connectBtn) connectBtn.disabled = true;
@@ -125,7 +125,7 @@
     log.innerHTML = "";
     try {
       addLog("info", "Requesting serial port…");
-      port = await navigator.serial.requestPort();
+      port = await MeshSerial.requestPort();
       await port.open({ baudRate: 115200 });
       writer = port.writable.getWriter();
       reader = port.readable.getReader();
diff --git a/internal/web/static/serial-setup.js b/internal/web/static/serial-setup.js
index 8e89fa7..a777983 100644
--- a/internal/web/static/serial-setup.js
+++ b/internal/web/static/serial-setup.js
@@ -39,7 +39,7 @@
   };
 
   // --- feature detection -------------------------------------------------
-  var hasSerial = "serial" in navigator;
+  var hasSerial = !!(window.MeshSerial && window.MeshSerial.supported);
   var hasEd25519 = !!(window.crypto && window.crypto.subtle);
   if (!hasSerial || !hasEd25519) {
     var u = $("unsupported");
@@ -276,7 +276,7 @@
     var decoder = new TextDecoder();
     try {
       addLog("info", "Requesting serial port…");
-      port = await navigator.serial.requestPort();
+      port = await MeshSerial.requestPort();
       await port.open({ baudRate: 115200 });
       writer = port.writable.getWriter();
       reader = port.readable.getReader();