Fix window_set_current_screen for maximized windows.

platform/linuxbsd/x11/display_server_x11.cpp

@@ -2055,7 +2055,7 @@ void DisplayServerX11::window_set_current_screen(int p_screen, WindowID p_window
 		return;
 	}
 
-	if (window_get_mode(p_window) == WINDOW_MODE_FULLSCREEN) {
+	if (window_get_mode(p_window) == WINDOW_MODE_FULLSCREEN || window_get_mode(p_window) == WINDOW_MODE_MAXIMIZED) {
 		Point2i position = screen_get_position(p_screen);
 		Size2i size = screen_get_size(p_screen);
 

platform/macos/display_server_macos.mm

@@ -1893,6 +1893,12 @@ void DisplayServerMacOS::window_set_current_screen(int p_screen, WindowID p_wind
 		was_fullscreen = true;
 	}
 
+	bool was_maximized = false;
+	if (!was_fullscreen && NSEqualRects([wd.window_object frame], [[wd.window_object screen] visibleFrame])) {
+		[wd.window_object zoom:nil];
+		was_maximized = true;
+	}
+
 	Rect2i srect = screen_get_usable_rect(p_screen);
 	Point2i wpos = window_get_position(p_window) - screen_get_position(window_get_current_screen(p_window));
 	Size2i wsize = window_get_size(p_window);
@@ -1901,6 +1907,10 @@ void DisplayServerMacOS::window_set_current_screen(int p_screen, WindowID p_wind
 	wpos = wpos.clamp(srect.position, srect.position + srect.size - wsize / 3);
 	window_set_position(wpos, p_window);
 
+	if (was_maximized) {
+		[wd.window_object zoom:nil];
+	}
+
 	if (was_fullscreen) {
 		// Re-enter fullscreen mode.
 		[wd.window_object toggleFullScreen:nil];

platform/windows/display_server_windows.cpp

@@ -1813,6 +1813,13 @@ void DisplayServerWindows::window_set_current_screen(int p_screen, WindowID p_wi
 		Size2 size = screen_get_size(p_screen);
 
 		MoveWindow(wd.hWnd, pos.x, pos.y, size.width, size.height, TRUE);
+	} else if (wd.maximized) {
+		Point2 pos = screen_get_position(p_screen) + _get_screens_origin();
+		Size2 size = screen_get_size(p_screen);
+
+		ShowWindow(wd.hWnd, SW_RESTORE);
+		MoveWindow(wd.hWnd, pos.x, pos.y, size.width, size.height, TRUE);
+		ShowWindow(wd.hWnd, SW_MAXIMIZE);
 	} else {
 		Rect2i srect = screen_get_usable_rect(p_screen);
 		Point2i wpos = window_get_position(p_window) - screen_get_position(window_get_current_screen(p_window));