AppImage window issue

The appImage shuts down (new start of SmallBASIC.AppImage needed) after pressed CTRL + B three times
 (1st and 2nd CTRL+ B doesn't work). This issue is with code using `w = window()`

```
w = window()
w.setSize(800, 680)

rect 0,0,799,599,8

rect 0, 0, 160, 160, 1 filled
rect 160, 160, 320, 320, 2 filled
rect 160, 0, 320, 160, 3 filled
rect 0, 160, 160, 320, 4 filled
```