diff --git a/portprotonqt/game_card.py b/portprotonqt/game_card.py
index 0ef20c1..eef003f 100644
--- a/portprotonqt/game_card.py
+++ b/portprotonqt/game_card.py
@@ -1,6 +1,7 @@
 from PySide6.QtGui import QPainter, QColor, QDesktopServices
 from PySide6.QtCore import Signal, Property, Qt, QUrl
 from PySide6.QtWidgets import QFrame, QGraphicsDropShadowEffect, QVBoxLayout, QWidget, QStackedLayout, QLabel
+from collections.abc import Callable
 from portprotonqt.image_utils import load_pixmap_async, round_corners
 from portprotonqt.localization import _
 from portprotonqt.config_utils import read_favorites, save_favorites, read_display_filter, read_theme_from_config
@@ -9,6 +10,8 @@ from portprotonqt.custom_widgets import ClickableLabel
 from portprotonqt.portproton_api import PortProtonAPI
 from portprotonqt.downloader import Downloader
 from portprotonqt.animations import GameCardAnimations
+from typing import cast
+
 
 class GameCard(QFrame):
     borderWidthChanged = Signal()
@@ -441,9 +444,10 @@ class GameCard(QFrame):
             self.update_scale()
             self.scaleChanged.emit()
 
-    borderWidth = Property(int, getBorderWidth, setBorderWidth, notify=borderWidthChanged)
-    gradientAngle = Property(float, getGradientAngle, setGradientAngle, notify=gradientAngleChanged)
-    scale = Property(float, getScale, setScale, notify=scaleChanged)
+    borderWidth = Property(int, getBorderWidth, setBorderWidth, None, "", notify=cast(Callable[[], None], borderWidthChanged))
+    gradientAngle = Property(float, getGradientAngle, setGradientAngle, None, "", notify=cast(Callable[[], None], gradientAngleChanged))
+    scale = Property(float, getScale, setScale, None, "", notify=cast(Callable[[], None], scaleChanged))
+
 
     def paintEvent(self, event):
         super().paintEvent(event)