"Use as featured image" not showing after deleting featured image

[alexmglover]

If a featured image is deleted, and then "Set Featured Image" is clicked, "Use as featured image" option is not available. In order for "Use as featured image" to show up, "Update" needs to be clicked to save the post/page without a Featured Image, then upon clicking "Set Featured Image" the option becomes available. I am not sure if this is intended behavior, but it seemed like a bug to me.

[PotterSys]

'Cause post_id != post_ID

[PotterSys]

I could trace the problem to admin-ajax.php. The function that creates the link for the upload has a global $post_ID. However, the set-post-thumbnail case have a $post_id (yes, 2 different variable names).

As a first attempt to fix it, just adding $post_ID = $post_id; below line 1465 fixes the bug. Another option (way more cool) is changing the variable name in set-post-thumbnail; but there's no clue if this bug could flip (ie. : another function has global $post_id)

[PotterSys]

A more elegant solution: changing the name for the whole case

[markjaquith]

(In [14731]) Correctly set Featured Post Image link after removing/updating. fixes #13033. props PotterSys