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filter is not described

comment_form_submit_field filter-hook . WP 4.2.0

Filters the submit field for the comment form to display.

The submit field includes the submit button, hidden fields for the comment form, and any wrapper markup.

Usage

add_filter( 'comment_form_submit_field', 'filter_function_name_2876', 10, 2 );
function filter_function_name_2876( $submit_field, $args ){
	// filter...

	return $submit_field;
}
$submit_field(string)
HTML markup for the submit field.
$args(array)
Arguments passed to comment_form().

Where the hook is called

comment_form()
wp-includes/comment-template.php 2465
echo apply_filters( 'comment_form_submit_field', $submit_field, $args );

Where the hook is used (in WP core)

Does not used.