diff --git a/js/app.js b/js/app.js
index 28a98cb..25191b0 100644
--- a/js/app.js
+++ b/js/app.js
@@ -7722,16 +7722,21 @@ async function init() {
             hotkeyPushSilent = true;
             Bridge.suspendHotkeys();
 
-            // A combo already owned by another app via RegisterHotKey is
-            // swallowed by Windows — it is delivered to that app, never to us,
-            // so the capture would wait forever with no explanation. It also
-            // preventDefaults every keystroke while armed, so an abandoned
-            // capture freezes the app's keyboard. Time out and say why.
+            // Modifiers the user is currently holding. We DO receive the
+            // Ctrl/Shift/Alt keydowns; only the final key of a combo owned by
+            // another app is swallowed by Windows (routed to that app). So
+            // "modifiers held, then all released, no key ever arrived" is a
+            // precise signal that the combo is taken — reported on keyup, with
+            // no wait. See onKeyUp.
+            let heldMods = '';
+
+            // Fallback for "armed but nothing was pressed at all" (the user
+            // walked away). Also matters because the capture preventDefaults
+            // every keystroke while armed — an abandoned one would freeze the
+            // app's keyboard until Esc.
             const timer = setTimeout(() => {
                 finish(true);
-                toast('No combo captured. If you did press one, another app ' +
-                      'already owns it — Windows routes it there and we never ' +
-                      'see it. Try a different combo.', 'warning');
+                toast('Hotkey capture cancelled — no key was pressed.', 'warning');
             }, 10000);
 
             function finish(restore) {
@@ -7739,6 +7744,7 @@ async function init() {
                 btn.dataset.capturing = '';
                 btn.classList.remove('is-capturing');
                 document.removeEventListener('keydown', onKey, true);
+                document.removeEventListener('keyup', onKeyUp, true);
                 if (restore) {
                     btn.textContent = original;
                     // Cancelled / timed out: nothing changed, so re-register the
@@ -7753,7 +7759,17 @@ async function init() {
                 e.preventDefault();
                 e.stopPropagation();
                 const captured = autofillCaptureFromEvent(e);
-                if (captured === null)     return;          // still building
+                if (captured === null) {                    // still building
+                    if (e.ctrlKey || e.shiftKey || e.altKey || e.metaKey) {
+                        const p = [];
+                        if (e.ctrlKey)  p.push('Ctrl');
+                        if (e.altKey)   p.push('Alt');
+                        if (e.shiftKey) p.push('Shift');
+                        if (e.metaKey)  p.push('Win');
+                        heldMods = p.join('+');
+                    }
+                    return;
+                }
                 if (captured === 'cancel') { finish(true); return; }
                 if (captured === 'invalid'){
                     toast('Unsupported key — use a letter, digit or F-key', 'warning');
@@ -7790,7 +7806,23 @@ async function init() {
                 autofillPushHotkeys();   // re-register in Delphi
                 saveServerSettings();    // sync to server (debounced)
             }
+            // All modifiers released while still "building" = the key that
+            // followed them never reached us, i.e. Windows handed the combo to
+            // whichever app registered it. Say exactly that instead of leaving
+            // the user staring at "Press combo…".
+            function onKeyUp(e) {
+                if (!heldMods) return;
+                if (e.ctrlKey || e.shiftKey || e.altKey || e.metaKey) return;
+                const mods = heldMods;
+                finish(true);
+                // Worded so it holds whether they pressed a swallowed key or
+                // just tapped a modifier and let go.
+                toast('No key registered after ' + mods + '. If you did press one, ' +
+                      'another app already owns that combo — pick a different one.',
+                      'warning');
+            }
             document.addEventListener('keydown', onKey, true);
+            document.addEventListener('keyup', onKeyUp, true);
         });
     }
     bindHotkeyCapture('#settingAutofillFullCombo', 'full');