diff --git a/manimlib/window.py b/manimlib/window.py
index c8620b71..e24adbfb 100644
--- a/manimlib/window.py
+++ b/manimlib/window.py
@@ -28,6 +28,9 @@ class Window(PygletWindow):
         self.position = initial_position
         self.position = initial_position
 
+        if "size" in kwargs:
+            self.size = kwargs["size"]
+
         mglw.activate_context(window=self)
         self.timer = Timer()
         self.config = mglw.WindowConfig(ctx=self.ctx, wnd=self, timer=self.timer)