__construct()
admin_init()
array_pluck()
editor()
get_icon()
get_wpcf7_posts()
map_shortcodes()
save_meta()
setup_shortcodes()
third_party_shortcodes()
complex_elements()
enqueues()
$handlers
$shortcodes
array_pluck($key, $array)
editor($post, $metabox)
get_icon($key)
get_wpcf7_posts($by)
save_meta($post_id)
third_party_shortcodes($available_shortcodes)