find_posts_div() not showing results

Hello, I am using the find_posts_div() function in my plugin to allow users to select links.

I fired the function in admin_footer hook and opened the dialog in javascript with findPosts.open().

Problem is, the dialog does not show results, and always returns a “-1”, no matter which term I put into the search box.

I looked at the markup of the dialog in the Media section (when you attach a media file to a post or page) and compared to the markup in my plugin, and they are identical.

I’m on WordPress 3.5.

Any clue about why does this happen?