diff --git a/src/menu/videomenu.cpp b/src/menu/videomenu.cpp
index dcf594f96..5fa2b08ec 100644
--- a/src/menu/videomenu.cpp
+++ b/src/menu/videomenu.cpp
@@ -141,7 +141,7 @@ int ViewportScaledWidth(int width)
 	switch (vid_scalemode)
 	{
 	default:
-	case 0: return width;
+	case 0: return (width==0)?vid_defwidth:width;
 	case 1: return 320;
 	case 2: return 640;
 	case 3: return (int)roundf(width * 0.5f);
@@ -155,7 +155,7 @@ int ViewportScaledHeight(int height)
 	switch (vid_scalemode)
 	{
 	default:
-	case 0: return height;
+	case 0: return (height==0)?vid_defheight:height;
 	case 1: return 200;
 	case 2: return 400;
 	case 3: return (int)roundf(height * 0.5f);
diff --git a/src/posix/cocoa/i_video.mm b/src/posix/cocoa/i_video.mm
index e0f1e6c68..7a9222cd3 100644
--- a/src/posix/cocoa/i_video.mm
+++ b/src/posix/cocoa/i_video.mm
@@ -147,7 +147,7 @@ CUSTOM_CVAR(Bool, swtruecolor, TRUECOLOR_DEFAULT, CVAR_ARCHIVE | CVAR_GLOBALCONF
 	}
 }
 
-CUSTOM_CVAR(Bool, fullscreen, false, CVAR_ARCHIVE | CVAR_GLOBALCONFIG)
+CUSTOM_CVAR(Bool, fullscreen, false, CVAR_ARCHIVE | CVAR_GLOBALCONFIG | CVAR_NOINITCALL)
 {
 	extern int NewWidth, NewHeight, NewBits, DisplayBits;