diff --git a/Apps/Keyty/Sources/Keyty/Features/Visualizers/Keyboard/KeyboardVisualizerGroupView.swift b/Apps/Keyty/Sources/Keyty/Features/Visualizers/Keyboard/KeyboardVisualizerGroupView.swift
index ceee61b8..1670afdc 100644
--- a/Apps/Keyty/Sources/Keyty/Features/Visualizers/Keyboard/KeyboardVisualizerGroupView.swift
+++ b/Apps/Keyty/Sources/Keyty/Features/Visualizers/Keyboard/KeyboardVisualizerGroupView.swift
@@ -71,7 +71,14 @@ extension KeyboardVisualizerGroupView {
 // MARK: - NSView
 extension KeyboardVisualizerGroupView {
     var preferredSize: NSSize {
-        NSSize(width: self.baseSize.width * self.scale, height: self.baseSize.height * self.scale)
+        let scaledSize = NSSize(
+            width: self.baseSize.width * self.scale,
+            height: self.baseSize.height * self.scale
+        )
+        return NSSize(
+            width: max(0, scaledSize.width.rounded(.up)),
+            height: max(0, scaledSize.height.rounded(.up))
+        )
     }
 
     override var intrinsicContentSize: NSSize {
diff --git a/Apps/Keyty/Tests/KeytyTests/Features/Settings/Keyboard/KeyboardSettingsPreviewTests.swift b/Apps/Keyty/Tests/KeytyTests/Features/Settings/Keyboard/KeyboardSettingsPreviewTests.swift
index c7297d9e..b08137e1 100644
--- a/Apps/Keyty/Tests/KeytyTests/Features/Settings/Keyboard/KeyboardSettingsPreviewTests.swift
+++ b/Apps/Keyty/Tests/KeytyTests/Features/Settings/Keyboard/KeyboardSettingsPreviewTests.swift
@@ -9,6 +9,7 @@
 import XCTest
 @testable import Keyty
 
+@MainActor
 final class KeyboardSettingsPreviewTests: XCTestCase {
     private var store: InMemoryKeyValueStore!
     private var settings: KeyboardVisualizerSettings!