$screen = get_current_screen();
if($screen->id == 'edit-category') {
//здесь код
}
<?php
add_filter('admin_footer', 'screen_test');
function screen_test(){
$screen = get_current_screen();
if($screen->id == 'edit-category') {
?>
<script>
alert('Тест!');
</script>
<?php
}
}