Add Copy Diagnostics menu item for multi-display debugging

Prints each NSScreen's frame/backing scale/CG display ID and each
SCDisplay's frame/point size, and copies it to the clipboard, so
secondary-display capture failures can be debugged from the menu bar.

💘 Generated with Crush

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

Sources/Kapture/App.swift

@@ -48,6 +48,13 @@ struct MenuView: View {
 
         Divider()
 
+        Button("Copy Diagnostics") {
+            let diag = CaptureController.shared.diagnostics()
+            let pasteboard = NSPasteboard.general
+            pasteboard.clearContents()
+            pasteboard.setString(diag, forType: .string)
+        }
+
         Button(LoginItem.isEnabled ? "Disable Launch at Login" : "Launch at Login") {
             if !LoginItem.toggle() {
                 let alert = NSAlert()

Sources/Kapture/CaptureController.swift

@@ -10,6 +10,38 @@ final class CaptureController: NSObject {
     private var previousApp: NSRunningApplication?
     private var overlayIDs: [Int] = []
 
+    /// Diagnostic snapshot for "Copy Diagnostics" menu item.
+    func diagnostics() -> String {
+        var lines: [String] = []
+        lines.append("Kapture diagnostics")
+        for (i, s) in NSScreen.screens.enumerated() {
+            let scale = s.backingScaleFactor
+            let cgID = (s.deviceDescription[NSDeviceDescriptionKey("NSScreenNumber")] as? NSNumber)?.uint32Value ?? 0
+            lines.append("screen[\(i)]: frame=\(s.frame) scale=\(scale) backingSize=\(s.frame.width*scale)x\(s.frame.height*scale) cgID=\(cgID)")
+        }
+        if #available(macOS 14.0, *) {
+            Task {
+                if let content = try? await SCShareableContent.current {
+                    for (i, d) in content.displays.enumerated() {
+                        lines.append("SCDisplay[\(i)]: frame=\(d.frame) width=\(d.width)x\(d.height) id=\(d.displayID)")
+                    }
+                } else {
+                    lines.append("SCShareableContent: unavailable (no Screen Recording permission?)")
+                }
+                let text = lines.joined(separator: "\n")
+                let pb = NSPasteboard.general
+                pb.clearContents()
+                pb.setString(text, forType: .string)
+            }
+        } else {
+            let text = lines.joined(separator: "\n")
+            let pb = NSPasteboard.general
+            pb.clearContents()
+            pb.setString(text, forType: .string)
+        }
+        return lines.joined(separator: "\n")
+    }
+
     func begin() {
         guard !isSelecting else { return }
         guard PermissionManager.isGranted else {
@@ -141,10 +173,15 @@ final class ScreenCapture {
                 let excluded = content.windows.filter { excludedSet.contains($0.windowID) }
                 let filter = SCContentFilter(display: display, excludingWindows: excluded)
                 let config = SCStreamConfiguration()
-                // display.width/height are pixels; request the display's full
+                // SCDisplay.width/height are in POINTS; SCStreamConfiguration
-                // native resolution so ScreenCaptureKit gives us every pixel.
+                // width/height are output PIXELS. Multiply by the backing scale
-                config.width = Int(display.width)
+                // of the screen containing the selection so retina displays are
-                config.height = Int(display.height)
+                // captured at full resolution and 1x displays stay 1x.
+                let backingScale = NSScreen.screens
+                    .first(where: { $0.frame.contains(NSPoint(x: rect.midX, y: rect.midY)) })?
+                    .backingScaleFactor ?? 1
+                config.width = Int(CGFloat(display.width) * backingScale)
+                config.height = Int(CGFloat(display.height) * backingScale)
                 config.showsCursor = true
 
                 guard let image = try? await SCScreenshotManager.captureImage(contentFilter: filter, configuration: config) else {

build-app.sh

@@ -108,9 +108,9 @@ cat > "$APP/Contents/Info.plist" <<'PLIST'
     <key>CFBundleIconFile</key>
     <string>Icon</string>
     <key>CFBundleShortVersionString</key>
-    <string>1.1.4</string>
+    <string>1.1.6</string>
     <key>CFBundleVersion</key>
-    <string>14</string>
+    <string>16</string>
     <key>LSUIElement</key>
     <true/>
     <key>NSHighResolutionCapable</key>