From 2678606a203e96299c3b42270bf77a2a15e5dc19 Mon Sep 17 00:00:00 2001
From: Lawrence Chen <54008264+lawrencecchen@users.noreply.github.com>
Date: Tue, 17 Feb 2026 03:35:49 -0800
Subject: [PATCH] Fix omnibar tracking timeout using background queue (#46)

The 3-second safety net that posts a synthetic mouseUp to break out of
NSTextView's stuck tracking loop was dispatched on the main queue. Since
super.mouseDown blocks the main thread in the tracking loop, the timeout
could never fire. Use a background queue instead (NSApp.postEvent is
thread-safe). Use DispatchWorkItem.isCancelled for atomic cancellation.
---
 Sources/Panels/BrowserPanelView.swift | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/Sources/Panels/BrowserPanelView.swift b/Sources/Panels/BrowserPanelView.swift
index 3bde66de..566aad89 100644
--- a/Sources/Panels/BrowserPanelView.swift
+++ b/Sources/Panels/BrowserPanelView.swift
@@ -1742,19 +1742,20 @@ private final class OmnibarNativeTextField: NSTextField {
         } else {
             // Already editing — allow normal click-to-place-cursor and drag-to-select.
             // Guard against a stuck tracking loop by posting a synthetic mouseUp after
-            // a timeout so the main thread can't be blocked indefinitely.
-            var trackingFinished = false
-            DispatchQueue.main.asyncAfter(deadline: .now() + 3.0) { [weak self] in
-                guard !trackingFinished, let self, let window = self.window else { return }
-                #if DEBUG
-                dlog("browser.omnibarTrackingTimeout — forcing mouseUp")
-                #endif
+            // a timeout. IMPORTANT: must use a background queue because super.mouseDown
+            // blocks the main thread in NSTextView's tracking loop, so
+            // DispatchQueue.main.asyncAfter would never fire.
+            let cancelled = DispatchWorkItem { /* sentinel */ }
+            let windowNumber = window?.windowNumber ?? 0
+            let location = event.locationInWindow
+            DispatchQueue.global(qos: .userInteractive).asyncAfter(deadline: .now() + 3.0) {
+                guard !cancelled.isCancelled else { return }
                 if let fakeUp = NSEvent.mouseEvent(
                     with: .leftMouseUp,
-                    location: event.locationInWindow,
+                    location: location,
                     modifierFlags: [],
                     timestamp: ProcessInfo.processInfo.systemUptime,
-                    windowNumber: window.windowNumber,
+                    windowNumber: windowNumber,
                     context: nil,
                     eventNumber: 0,
                     clickCount: 1,
@@ -1764,7 +1765,7 @@ private final class OmnibarNativeTextField: NSTextField {
                 }
             }
             super.mouseDown(with: event)
-            trackingFinished = true
+            cancelled.cancel()
         }
     }