Why isn’t SendMessage/PostMessage working for minimized windows in Windows 11?

I'm using a Python script that utilizes the win32api module to send keystrokes to a specific window using PostMessage. Here's a simplified version of my code:

```python
import win32api
import win32con
import time
import random

def winapi(w, key):
win32api.PostMessage(w, win32con.WM_KEYDOWN, key, 0)
time.sleep(random.uniform(0.369420, 0.769420))
win32api.PostMessage(w, win32con.WM_KEYUP, key, 0)
```

This approach worked perfectly on Windows 10 and even on Linux with Proton. However, on Windows 11, I've found that the PostMessage and SendMessage functions only seem to work if the target window is maximized, regardless of whether it has focus or not. Has Windows 11 changed something at the API level that affects this functionality?