visual studio code maximize button doesn't work windows11

It is a reported issue, see Maximize/restore button is not responsive when Window Controls Overlay is enabled.

You can try disabling this setting (although it is disabled by default in Stable v1.71) to see if it helps:

Window > Experimental > Window Controls Overlay: Enabled

I am using windows 11 as well, and I just recently updated my vs code to the latest version. I will use pictures to explain my solution

1. Go to settings

2. Search for overlay in the settings page

3. Uncheck the checkbox below and restart vs-code

have you tried the F11 button? or the combination of CTRL + k -> Z Bye