CPTs not shown in settings

Hello, great plugin, does exactly what I need, but i noticed one issue:

In Sqhr_Link_Qr_Code and SQHR_QR_CODE_Settings_Setup you call get_post_types and pass an array:

$get_cpt_args = array(
‘public’ => true,
‘_builtin’ => true,
);

This causes only Posts and Pages to be returned.
Removing _builtin:

$get_cpt_args = array(
‘public’ => true,
// ‘_builtin’ => true,
);

Returns posts and pages and all custom post types.