Ticket #28627: 28627.diff

wp-admin/includes/revision.php

@@ -211 +211 @@
                 'fields' => wp_get_revision_ui_diff( $post->ID, $from, $selected_revision_id ),
         ));
 
-        return array(
+        $revisions_settings = array(
                 'postId'           => $post->ID,
                 'nonce'            => wp_create_nonce( 'revisions-ajax-nonce' ),
                 'revisionData'     => array_values( $revisions ),
@@ -222 +222 @@
                 'compareTwoMode'   => absint( $compare_two_mode ), // Apparently booleans are not allowed
                 'revisionIds'      => array_keys( $revisions ),
         );
+
+        /**
+         * Filter the revisions settings used for the revisions JS.
+         *
+         * @since 4.0.0
+         *
+         * @param array   $revisions_settings The settings array
+         * @param WP_Post $post               The original post object which owns the revisions
+         */
+        $revisions_settings = wp_parse_args( apply_filters( 'revisions_settings_for_js', $revisions_settings, $post ), $revisions_settings );
+
+        return $revisions_settings;
 }