diff --git a/Sources/Kapture/CaptureController.swift b/Sources/Kapture/CaptureController.swift
index 32f2ea1..95e0691 100644
--- a/Sources/Kapture/CaptureController.swift
+++ b/Sources/Kapture/CaptureController.swift
@@ -301,8 +301,11 @@ final class CaptureController: NSObject {
                 }
                 return event
             }
-            // Drag: grow the marquee
+            // Drag: grow the marquee — but only after real movement, so a
+            // click's micro-jitter keeps the hovered window eligible.
             guard let start = marqueeStart else { return nil }
+            let distance = hypot(appKitPoint.x - start.x, appKitPoint.y - start.y)
+            guard distance >= 4 else { return nil }
             let rect = NSRect(
                 x: min(start.x, appKitPoint.x),
                 y: min(start.y, appKitPoint.y),
@@ -443,28 +446,43 @@ final class ScreenCapture {
             let detected = Self.detectCornerRadius(of: result)
             let radius = min(max((detected.map { $0 * 1.23 + 2.6 }) ?? (10 * scaleX), 4), 40)
             CaptureController.log("corners: detected=\(detected.map { String(format: "%.1f", $0) } ?? "nil") using=\(Int(radius))px")
+            // Anti-aliased gray mask: supersample 3x, downsample, then draw
+            // the image through it ONCE at 1x (no content resampling blur).
             let ss = 3
             let W = result.width * ss, H = result.height * ss
-            guard let hiCtx = CGContext(
+            guard let hiMask = CGContext(
                 data: nil, width: W, height: H,
                 bitsPerComponent: 8, bytesPerRow: 0,
-                space: CGColorSpaceCreateDeviceRGB(),
-                bitmapInfo: CGImageAlphaInfo.premultipliedLast.rawValue
+                space: CGColorSpaceCreateDeviceGray(),
+                bitmapInfo: CGImageAlphaInfo.none.rawValue
             ) else { return result }
-            hiCtx.addPath(CGPath(roundedRect: CGRect(x: 0, y: 0, width: W, height: H), cornerWidth: radius * CGFloat(ss), cornerHeight: radius * CGFloat(ss), transform: nil))
-            hiCtx.clip()
-            hiCtx.interpolationQuality = .high
-            hiCtx.draw(result, in: CGRect(x: 0, y: 0, width: W, height: H))
-            guard let hi = hiCtx.makeImage(),
-                  let downCtx = CGContext(
+            hiMask.setFillColor(CGColor(gray: 1, alpha: 1))
+            hiMask.fill(CGRect(x: 0, y: 0, width: W, height: H))
+            hiMask.setFillColor(CGColor(gray: 0, alpha: 1))
+            let cornerPath = CGMutablePath()
+            cornerPath.addRect(CGRect(x: 0, y: 0, width: W, height: H))
+            cornerPath.addRoundedRect(in: CGRect(x: 0, y: 0, width: W, height: H), cornerWidth: radius * CGFloat(ss), cornerHeight: radius * CGFloat(ss), transform: .identity)
+            hiMask.addPath(cornerPath)
+            hiMask.fillPath(using: .evenOdd)
+            guard let hiMaskImg = hiMask.makeImage(),
+                  let downMask = CGContext(
+                data: nil, width: result.width, height: result.height,
+                bitsPerComponent: 8, bytesPerRow: 0,
+                space: CGColorSpaceCreateDeviceGray(),
+                bitmapInfo: CGImageAlphaInfo.none.rawValue
+            ) else { return result }
+            downMask.interpolationQuality = .high
+            downMask.draw(hiMaskImg, in: CGRect(x: 0, y: 0, width: result.width, height: result.height))
+            guard let mask1x = downMask.makeImage(),
+                  let ctx = CGContext(
                 data: nil, width: result.width, height: result.height,
                 bitsPerComponent: 8, bytesPerRow: 0,
                 space: CGColorSpaceCreateDeviceRGB(),
                 bitmapInfo: CGImageAlphaInfo.premultipliedLast.rawValue
             ) else { return result }
-            downCtx.interpolationQuality = .high
-            downCtx.draw(hi, in: CGRect(x: 0, y: 0, width: result.width, height: result.height))
-            if let masked = downCtx.makeImage() {
+            ctx.clip(to: CGRect(x: 0, y: 0, width: result.width, height: result.height), mask: mask1x)
+            ctx.draw(result, in: CGRect(x: 0, y: 0, width: result.width, height: result.height))
+            if let masked = ctx.makeImage() {
                 result = masked
             }
         }
diff --git a/build-app.sh b/build-app.sh
index 3676233..04ab41e 100755
--- a/build-app.sh
+++ b/build-app.sh
@@ -108,9 +108,9 @@ cat > "$APP/Contents/Info.plist" <<'PLIST'
     <key>CFBundleIconFile</key>
     <string>Icon</string>
     <key>CFBundleShortVersionString</key>
-    <string>1.8.5</string>
+    <string>1.8.6</string>
     <key>CFBundleVersion</key>
-    <string>85</string>
+    <string>86</string>
     <key>LSUIElement</key>
     <true/>
     <key>NSHighResolutionCapable</key>