Per T270202#6767750 the input should expand when focused before WVUI
loads. However, the input should *only* expand when `showThumbnail` is
`true` in `$wgVectorWvuiSearchOptions` to match how its done in WVUI
where it takes into account the size of the thumbnails. When
`showThumbnail` is false, it should not expand as the input won't match
WVUI and the WVUI load transition will be jarring.
To test locally, toggle between true/false in your LocalSettings.php:
```
$wgVectorWvuiSearchOptions = [
"showThumbnail" => false,
];
```
Bug: T270202
Change-Id: I70277c1082a504fbd5f6023e9873e8071de7e35d