Reject window captures that composite extra windows

ScreenCaptureKit's desktopIndependentWindow filter can include owned
child windows (e.g. an app dialog plus its parent), producing a capture
much larger than the picked window. Detect the overflow by comparing the
returned image size against the window's frame and fall back to the
screen crop with rounded mask. Hover changes are logged with the picked
window id and tracked count for diagnosis.

💘 Generated with Crush

Assisted-by: Crush:deepseek-v4-flash-0731

Sources/Kapture/CaptureController.swift

@@ -287,6 +287,11 @@ final class CaptureController: NSObject {
                 let window = topmostWindowContaining(appKitPoint)
                 if window?.frame != hoverFrame {
                     hoverWindow = window
+                    if let w = window {
+                        CaptureController.log("hover: picked id=\(w.id) frame=\(w.frame) (tracked=\(trackedWindows.count))")
+                    } else {
+                        CaptureController.log("hover: none (tracked=\(trackedWindows.count))")
+                    }
                     renderOverlays()
                 }
                 return event
@@ -463,9 +468,21 @@ final class ScreenCapture {
                         contentFilter: SCContentFilter(desktopIndependentWindow: scWindow),
                         configuration: windowConfig
                     ) {
-                        CaptureController.log("capture: WINDOW id=\(windowID) image=\(windowImage.width)x\(windowImage.height) (native alpha corners)")
-                        completion(windowImage)
-                        return
+                        let expectedW = CGFloat(scWindow.frame.width) * backingScale
+                        let expectedH = CGFloat(scWindow.frame.height) * backingScale
+                        let overflow = max(
+                            CGFloat(windowImage.width) / max(expectedW, 1),
+                            CGFloat(windowImage.height) / max(expectedH, 1)
+                        )
+                        if overflow > 1.35 {
+                            // SCKit composited extra windows (owned popups etc.)
+                            // — reject and use the screen crop instead.
+                            CaptureController.log("capture: WINDOW id=\(windowID) overflow=\(overflow) (\(windowImage.width)x\(windowImage.height) vs \(Int(expectedW))x\(Int(expectedH))) — rejecting, using crop+mask")
+                        } else {
+                            CaptureController.log("capture: WINDOW id=\(windowID) image=\(windowImage.width)x\(windowImage.height) (native alpha corners)")
+                            completion(windowImage)
+                            return
+                        }
                     }
                     CaptureController.log("capture: window filter failed for id=\(windowID) — falling back to crop+mask")
                 }

build-app.sh

@@ -108,9 +108,9 @@ cat > "$APP/Contents/Info.plist" <<'PLIST'
     <key>CFBundleIconFile</key>
     <string>Icon</string>
     <key>CFBundleShortVersionString</key>
-    <string>1.8.0</string>
+    <string>1.8.1</string>
     <key>CFBundleVersion</key>
-    <string>80</string>
+    <string>81</string>
     <key>LSUIElement</key>
     <true/>
     <key>NSHighResolutionCapable</key>