Rely on srcset to select best image size; only add Story Page as available image size

Author: westonruter

includes/class-amp-story-media.php

@@ -205,9 +205,7 @@ public static function ensure_correct_poster_size( $image, $attachment_id, $size
 	/**
 	 * Adds a new max image size to the image sizes available.
 	 *
-	 * In the AMP story editor, when selecting Background Media,
-	 * it will use this custom image size.
-	 * This filter will also make it available in the Image block's 'Image Size' <select> element.
+	 * This filter makes this custom image size available in the Image block's 'Image Size' <select> element.
 	 *
 	 * @param array $image_sizes {
 	 *     An associative array of image sizes.
@@ -218,15 +216,10 @@ public static function ensure_correct_poster_size( $image, $attachment_id, $size
 	 * @return array $image_sizes The filtered image sizes.
 	 */
 	public static function add_new_max_image_size( $image_sizes ) {
-		$full_size_name = __( 'Story Max Size', 'amp' );
 
-		if ( isset( $_POST['action'] ) && ( 'query-attachments' === $_POST['action'] || 'upload-attachment' === $_POST['action'] ) ) { // phpcs:ignore WordPress.Security.NonceVerification.Missing
-			$image_sizes[ self::MAX_IMAGE_SIZE_SLUG ] = $full_size_name;
-		} elseif ( get_post_type() && AMP_Story_Post_Type::POST_TYPE_SLUG === get_post_type() ) {
-			$image_sizes[ self::MAX_IMAGE_SIZE_SLUG ] = $full_size_name;
-			unset( $image_sizes['full'] );
+		if ( AMP_Story_Post_Type::POST_TYPE_SLUG === get_post_type() ) {
+			$image_sizes[ self::MAX_IMAGE_SIZE_SLUG ] = __( 'Story Page', 'amp' );
 		}
-
 		return $image_sizes;
 	}