Ticket #39912: 39912.diff

src/wp-includes/js/tinymce/plugins/wpeditimage/plugin.js

@@ -389 +389 @@
 
                 dom.setAttribs( imageNode, attrs );
 
+                // Preserve empty alt attributes.
+                if ( ! dom.getAttrib( imageNode, 'alt' ) ) {
+                        dom.$$( imageNode ).attr( 'alt', '' );
+                }
+
                 linkAttrs = {
                         href: imageData.linkUrl,
                         rel: imageData.linkRel || null,
@@ -1026 +1031 @@
         editor.on( 'beforeGetContent', function( event ) {
                 if ( event.format !== 'raw' ) {
                         editor.$( 'img[id="__wp-temp-img-id"]' ).attr( 'id', null );
-                }       
+                }
         });
 
         editor.on( 'BeforeSetContent', function( event ) {