Pre WP 4.9
if( ! function_exists( 'fix_no_editor_on_posts_page' ) ) {
/**
* Add the wp-editor back into WordPress after it was removed in 4.2.2.
*
* @param Object $post
* @return void
*/
function fix_no_editor_on_posts_page( $post ) {
if( isset( $post ) && $post->ID != get_option('page_for_posts') ) {
return;
}
remove_action( 'edit_form_after_title', '_wp_posts_page_notice' );
add_post_type_support( 'page', 'editor' );
}
add_action( 'edit_form_after_title', 'fix_no_editor_on_posts_page', 0 );
}
WP 4.9
if( ! function_exists( 'fix_no_editor_on_posts_page' ) ) {
function fix_no_editor_on_posts_page( $post_type, $post ) {
if( isset( $post ) && $post->ID != get_option('page_for_posts') ) {
return;
}
remove_action( 'edit_form_after_title', '_wp_posts_page_notice' );
add_post_type_support( 'page', 'editor' );
}
add_action( 'add_meta_boxes', 'fix_no_editor_on_posts_page', 0, 2 );
}