No idea why the change of folder name makes a difference, but you should add jquery as dependency in your enqueue
wp_enqueue_script(
'wtfjs',
plugins_url( '/js/wtf.js' , __FILE__),
array('jquery')
);
No idea why the change of folder name makes a difference, but you should add jquery as dependency in your enqueue
wp_enqueue_script(
'wtfjs',
plugins_url( '/js/wtf.js' , __FILE__),
array('jquery')
);