Regression noticed in this line:
3f97d98bff/ui/tabs/downloads.slint (L77)
The following used to work:
```slint
import { Button, VerticalBox } from "std-widgets.slint";
export component Demo {
in property <[int]> mods;
VerticalBox {
alignment: start;
for xxx in true ? mods : [] : HorizontalLayout { alignment: center; Button { text: "OK!"; } }
}
}
```
But we fixed array conversion and this caused a regression with empty
array