Updated Customize UI (markdown)

Customize-UI.md

@@ -191,6 +191,16 @@ By default, commands are not executed in a shell. You may explicitly call a shel
         command: [ "bash", "-c", "echo \"hello this is $USER\"" ]
 ```
 
+#### VirtualKey
+Send a keyboard press or release event.
+```yaml
+      - type: VirtualKey
+        keycode: XF86Launch3
+        action: Press
+```
+
+Available key codes are listed [here](https://github.com/galister/wlx-overlay-s/blob/83ae79821552cee24de7b0c4c2d6d82f16f90847/src/hid/mod.rs#L322-L473). Action can be `Press` or `Release`.
+
 #### Toast
 ```yaml
       - type: Toast