Twenty Fifteen: The search submit button CSS is display: none; That should be CSS like screen reader only.

[rianrietveld]

The search widgets has a class search-submit hiding the submit button with display:none;

.search-form input[type="submit"] {
display: none;
}

This way the button is always hidden, also for all assistive technology.

Maybe it's better to change that into a screen-reader-only functionality by adding the class name to the screen-reader-tex definition in style.css, like

.screen-reader-text, .search-form input[type="submit"] {
	clip: rect(1px, 1px, 1px, 1px);
	height: 1px;
	overflow: hidden;
	position: absolute !important;
	width: 1px;
}

[johnbillion]

Thanks for the patch Rian!

I think a better way to address this is to add the screen-reader-text class to the search submit button. That way we stick to one class for screen reader text and use it on all elements which act as assistive text for screen readers.

[rianrietveld]

But wouldn't add the class screen-reader-text to the search submit button influence other themes, that maybe have a visible submit button, because the search form is a core widget in general-tempate.php?

[mattwiebe]

The search form would have to be implemented locally for the theme with a searchform.php file to customize the markup to achieve the desired result, or we could use the get_search_form filter.

Patch incoming for the latter. Otherwise Rian's patch (except for the font-family error) would work for me.

[johnbillion]

This isn't ideal, but it saves us redefining the search form via searchform.php.

[johnbillion]

In 30053:

Make the Twenty Fifteen search form submit button screen reader accessible rather than hidden to all users. Fixes #30110. Props mattweibe, rianrietveld.