When a registered user (as subscriber) tries to upload an image, it shows the 100% progress bar and returns no errors, but It doesn’t show on the activity stream. (If uploaded with text, only the text is shown)
And if you click on the image to edit it, it shows as UNDEFINED in the URL ex: mydomain.com/undefined
But when a registered user (as author or above) uploads the image, it works fine.
Any idea why is there this restriction for subscribers???