wp-content/themes/twentyfifteen/functions.php:591Add a screen-reader-text class to the search form's submit button.
$htmlstringstringfunction twentyfifteen_search_form_modify( $html ) { return str_replace( 'class="search-submit"', 'class="search-submit screen-reader-text"', $html );}Introduced in Twenty Fifteen 1.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-content/themes/twentyfifteen/functions.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.