WordPress 3.5 how to determine if user is on category listing or category edit screen?

Question

I have a custom bit of code that I need to place on the category edit screen but not on the manage categories screen.

Prior to WordPress 3.5, I was able to set a global $action variable to check for action="edit" and place my code.

The same action variable returns empty in 3.5

Answer 1

if(is_admin() && isset($_GET['taxonomy']) && $_GET['taxonomy'] == 'category' && isset($_GET['tag_ID']) {
    // place your code here
}