In wp-admin/options-media.php, there are a few lines that go:
<?php if ( isset( $GLOBALS['wp_settings']['media']['embeds'] ) ) : ?>
<h3 class="title"><?php _e('Embeds') ?></h3>
<table class="form-table">
<?php do_settings_fields( 'media', 'embeds' ); ?>
</table>
<?php endif; ?>
’embeds’ and “embeds” are nowhere else to be found in the WP code base. Might anyone know what it’s for?
Per the two comments by Rarst and myself, the variable itself is is potentially populated by
add_settings_field(), and the related logic is present for historical/backwards compatibility reasons. (There used to be fields in this area.)The related ticket and changeset for reference: