Bug 220580

Created attachment 417510 [details]
Testcase

We found a regression from r257839.

Here is how to reproduce:
1. Open the attached html with MiniBrowser
2. Push Enter key

Expected result:
Newly appeared "Menu Item" button should have focus.

Actual result:
Newly appeared "Menu Item" button doesn't have focus.

Reproduced environment:
- WinCairo MiniBrowser (r271389)

Note:
- I confirmed that reverting r257839 solves the issue.
- Chrome (87.0.4280.141) and Firefox (84.0.1) on Windows don't have this issue
- I didn't test Safari, but because the changed code in r257839 is platform-independent code, I hope it can be reproduced in Safari too.

Attached test case description:
"Menu Item" button is at first invisible, because the div which contains the button is "display:none".
When Enter key is hit, "open" class is added, and it should overwrite "display" with "block".
Then we call "focus" on the button. Because button is visible now, it should have focus.

// open menu
document.querySelector('.menu').classList.add('open');
// focus on menu item
document.querySelector('.menu-item').focus();

<div class="menu">
    <ul>
        <li>
            <button class="menu-item">Menu Item</button>
        </li>
    </ul>
</div>

.menu {
    display: none;
    background: #000;
}
.open {
    display: block;
}