diff --git a/lib/class-wp-rest-image-editor-controller.php b/lib/class-wp-rest-image-editor-controller.php
index 76afc5edc9a563..66c8531e02d7ed 100644
--- a/lib/class-wp-rest-image-editor-controller.php
+++ b/lib/class-wp-rest-image-editor-controller.php
@@ -300,6 +300,12 @@ public function apply_edits( $request ) {
 			return $new_attachment_id;
 		}
 
+		if ( defined( 'REST_REQUEST' ) && REST_REQUEST ) {
+			// Set a custom header with the attachment_id.
+			// Used by the browser/client to resume creating image sub-sizes after a PHP fatal error.
+			header( 'X-WP-Upload-Attachment-ID: ' . $new_attachment_id );
+		}
+
 		// Generate image sub-sizes and meta.
 		$new_image_meta = wp_generate_attachment_metadata( $new_attachment_id, $saved['path'] );
 
diff --git a/packages/block-library/src/image/image-editor.js b/packages/block-library/src/image/image-editor.js
index 361355ee8d9a5d..d3bc19f6ee98dc 100644
--- a/packages/block-library/src/image/image-editor.js
+++ b/packages/block-library/src/image/image-editor.js
@@ -195,7 +195,7 @@ export default function ImageEditor( {
 		attrs.src = url;
 
 		apiFetch( {
-			path: `wp/v2/media/${ id }/edit`,
+			path: `/wp/v2/media/${ id }/edit`,
 			method: 'POST',
 			data: attrs,
 		} )