Window Focus Desync #2756
Description
I have encountered the following issue using LWJGL 3.3.6 (the latest stable version) on Windows 10:
When I create a GLFW window while dragging another window, GLFW thinks the window is focused, even though it's not.
Both glfwGetWindowAttrib and windowFocusCallback return the wrong value
2025-08-12.01-40-57.mp4
The code
import static org.lwjgl.glfw.GLFW.*;
public class Test2 {
public static long handle;
public static void main(String[] args) {
try {
Thread.sleep(500);
}catch (Exception e) {}
glfwInit();
glfwDefaultWindowHints();
glfwWindowHint(GLFW_VISIBLE, GLFW_FALSE);
handle = glfwCreateWindow(640, 480, "Test", 0, 0);
glfwSetWindowFocusCallback(handle, Test2::focusCallback);
glfwShowWindow(handle);
while(true) {
glfwPollEvents();
if(glfwWindowShouldClose(handle)) {
break;
}
glfwSetWindowTitle(handle, "Focused: " + isFocused());
try {
Thread.sleep(10);
}catch (Exception e) {}
}
}
public static boolean isFocused() {
return glfwGetWindowAttrib(handle, GLFW_FOCUSED) != 0;
}
public static void focusCallback(long window, boolean focused) {
System.out.println("Focus changed: " + focused);
}
}