i get that error trying to attach a image.
wordpress and attachments are both newest versions.

Chrome error:
Uncaught TypeError: Cannot read property 'url' of undefined post-new.php:579
(anonymous function) post-new.php:579
T.each.T.forEach load-scripts.php:394
r.(anonymous function) load-scripts.php:420
(anonymous function) post-new.php:569
g.Events.trigger load-scripts.php:404
f.extend._onModelEvent load-scripts.php:419
g.Events.trigger load-scripts.php:404
f.view.Toolbar.Select.f.view.Toolbar.extend.clickSelect load-scripts.php:437
f.view.Button.f.View.extend.click load-scripts.php:437
v.event.dispatch load-scripts.php:2
o.handle.u