I tried 1.4 and the svn and the git ‘trunk’ versions (don’t know if those are different). But it’s not working for me.
There’s no link “Set as secondary image” in the image ‘menu/popup’.
I’m using the Dutch version of wordpress 3.5.1 . Could it be a localization problem or something different?
Also i’m not installing it as a plugin but i’m using the class in a plugin i build myself, could this cause a problem? (My plugin instantiates an instance in the load-post.php hook but i also tried instantiating in function.php with no difference).
So could one of these things cause issues or is the class not working in 3.5.1 version yet?