diff --git a/src/client/inputhandler.cpp b/src/client/inputhandler.cpp
index ae994b8b5..a30c818a7 100644
--- a/src/client/inputhandler.cpp
+++ b/src/client/inputhandler.cpp
@@ -118,8 +118,14 @@ bool MyEventReceiver::OnEvent(const SEvent &event)
 		const KeyPress keyCode(event.KeyInput);
 		if (keyCode == getKeySetting("keymap_fullscreen")) {
 			if (event.KeyInput.PressedDown && !fullscreen_is_down) {
-				bool fullscreen = RenderingEngine::get_raw_device()->isFullscreen();
-				g_settings->setBool("fullscreen", !fullscreen);
+				IrrlichtDevice *device = RenderingEngine::get_raw_device();
+
+				bool new_fullscreen = !device->isFullscreen();
+				// Only update the setting if toggling succeeds - it always fails
+				// if Minetest was built without SDL.
+				if (device->setFullscreen(new_fullscreen)) {
+					g_settings->setBool("fullscreen", new_fullscreen);
+				}
 			}
 			fullscreen_is_down = event.KeyInput.PressedDown;
 			return true;
diff --git a/src/client/renderingengine.cpp b/src/client/renderingengine.cpp
index b0033c0e2..e7ba333d2 100644
--- a/src/client/renderingengine.cpp
+++ b/src/client/renderingengine.cpp
@@ -489,11 +489,14 @@ void RenderingEngine::autosaveScreensizeAndCo(
 	// we do not want to save the thing. This allows users to also manually change
 	// the settings.
 
+	// Don't save the fullscreen size, we want the windowed size.
+	bool fullscreen = RenderingEngine::get_raw_device()->isFullscreen();
 	// Screen size
 	const irr::core::dimension2d<u32> current_screen_size =
 		RenderingEngine::get_video_driver()->getScreenSize();
 	// Don't replace good value with (0, 0)
-	if (current_screen_size != irr::core::dimension2d<u32>(0, 0) &&
+	if (!fullscreen &&
+			current_screen_size != irr::core::dimension2d<u32>(0, 0) &&
 			current_screen_size != initial_screen_size) {
 		g_settings->setU16("screen_w", current_screen_size.Width);
 		g_settings->setU16("screen_h", current_screen_size.Height);