diff --git a/wp-admin/edit-form-advanced.php b/wp-admin/edit-form-advanced.php
index 2db7e90c5f..07c2dfe129 100644
--- a/wp-admin/edit-form-advanced.php
+++ b/wp-admin/edit-form-advanced.php
@@ -17,6 +17,17 @@ if ( !defined('ABSPATH') )
  */
 global $post_type, $post_type_object, $post;
 
+if ( is_multisite() ) {
+	add_action( 'admin_footer', '_admin_notice_post_locked' );
+} else {
+	$check_users = get_users( array( 'fields' => 'ID', 'number' => 2 ) );
+
+	if ( count( $check_users ) > 1 )
+		add_action( 'admin_footer', '_admin_notice_post_locked' );
+
+	unset( $check_users );
+}
+
 wp_enqueue_script('post');
 $_wp_editor_expand = $_content_editor_dfw = false;
 
diff --git a/wp-admin/post-new.php b/wp-admin/post-new.php
index ac80f1350f..46e402ab0c 100644
--- a/wp-admin/post-new.php
+++ b/wp-admin/post-new.php
@@ -63,24 +63,17 @@ if ( ! current_user_can( $post_type_object->cap->edit_posts ) || ! current_user_
 }
 
 // Schedule auto-draft cleanup
-if ( ! wp_next_scheduled( 'wp_scheduled_auto_draft_delete' ) )
+if ( ! wp_next_scheduled( 'wp_scheduled_auto_draft_delete' ) ) {
 	wp_schedule_event( time(), 'daily', 'wp_scheduled_auto_draft_delete' );
-
-wp_enqueue_script( 'autosave' );
-
-if ( is_multisite() ) {
-	add_action( 'admin_footer', '_admin_notice_post_locked' );
-} else {
-	$check_users = get_users( array( 'fields' => 'ID', 'number' => 2 ) );
-
-	if ( count( $check_users ) > 1 )
-		add_action( 'admin_footer', '_admin_notice_post_locked' );
-
-	unset( $check_users );
 }
 
-// Show post form.
 $post = get_default_post_to_edit( $post_type, true );
 $post_ID = $post->ID;
-include( ABSPATH . 'wp-admin/edit-form-advanced.php' );
+
+/** This filter is documented in wp-admin/post.php */
+if ( apply_filters( 'replace_editor', false, $post ) !== true ) {
+	wp_enqueue_script( 'autosave' );
+	include( ABSPATH . 'wp-admin/edit-form-advanced.php' );
+}
+
 include( ABSPATH . 'wp-admin/admin-footer.php' );
diff --git a/wp-admin/post.php b/wp-admin/post.php
index cf2bee5790..dbfb156430 100644
--- a/wp-admin/post.php
+++ b/wp-admin/post.php
@@ -144,6 +144,18 @@ case 'edit':
 		$post_new_file = "post-new.php?post_type=$post_type";
 	}
 
+	/**
+	 * Allows replacement of the editor.
+	 *
+	 * @since 4.9.0
+	 *
+	 * @param boolean      Whether to replace the editor. Default false.
+	 * @param object $post Post object.
+	 */
+	if ( apply_filters( 'replace_editor', false, $post ) === true ) {
+		break;
+	}
+
 	if ( ! wp_check_post_lock( $post->ID ) ) {
 		$active_post_lock = wp_set_post_lock( $post->ID );
 
@@ -151,17 +163,6 @@ case 'edit':
 			wp_enqueue_script('autosave');
 	}
 
-	if ( is_multisite() ) {
-		add_action( 'admin_footer', '_admin_notice_post_locked' );
-	} else {
-		$check_users = get_users( array( 'fields' => 'ID', 'number' => 2 ) );
-
-		if ( count( $check_users ) > 1 )
-			add_action( 'admin_footer', '_admin_notice_post_locked' );
-
-		unset( $check_users );
-	}
-
 	$title = $post_type_object->labels->edit_item;
 	$post = get_post($post_id, OBJECT, 'edit');
 
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 1d09cf55e2..f4e97b77b1 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.9-beta1-41828';
+$wp_version = '4.9-beta1-41829';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.