Only set the poster attribute automatically for videos when the image does not match the default mime-type icon. wp_prepare_attachment_for_js() is used in multiple contexts. This context requires disambiguation.

See [27659].



git-svn-id: https://develop.svn.wordpress.org/trunk@27980 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/js/media-editor.js

@@ -189,7 +189,7 @@
 			shortcode = {};
 
 			if ( 'video' === type ) {
-				if ( attachment.image ) {
+				if ( attachment.image && -1 === attachment.image.src.indexOf( attachment.icon ) ) {
 					shortcode.poster = attachment.image.src;
 				}