a modal window doesn't focus on its first focusable child

Steps to Reproduce

    <window mode="modal" title="modal">
        focus on the first focusable component:
        <textbox/>
    </window>

1. click out of the browser
2. click anywhere on the page (don't click the textbox)

Current Result

no focus on the textbox

Expected Result

focus on the textbox

Debug Information

• before 9.5.1.4, this bug doesn't happen

Workaround