Bootstrap with separate js File

wp_enqueue_script( 'ecp_admin_js', plugins_url('/js/script.js' , __FILE__), array(), '1.0', false );

Has to be:

wp_enqueue_script( 'ecp_admin_js', plugins_url('/js/script.js' , __FILE__), array(), '1.0', true );

Only if set to true the Script is added to the Footer (above closing body-Tag)!

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