diff --git a/README.md b/README.md
index 339b70e7..64924b7a 100644
--- a/README.md
+++ b/README.md
@@ -118,7 +118,7 @@ information on what to include when reporting a bug.
 
 ## Changelog
 
-There is nothing here yet.
+ - [X11] Bugfix: `glfwFocusWindow` could terminate on older WMs or without a WM
 
 
 ## Contact
diff --git a/src/x11_window.c b/src/x11_window.c
index 522c293c..ed4e2513 100644
--- a/src/x11_window.c
+++ b/src/x11_window.c
@@ -2457,7 +2457,7 @@ void _glfwPlatformFocusWindow(_GLFWwindow* window)
 {
     if (_glfw.x11.NET_ACTIVE_WINDOW)
         sendEventToWM(window, _glfw.x11.NET_ACTIVE_WINDOW, 1, 0, 0, 0, 0);
-    else
+    else if (_glfwPlatformWindowVisible(window))
     {
         XRaiseWindow(_glfw.x11.display, window->x11.handle);
         XSetInputFocus(_glfw.x11.display, window->x11.handle,