Not working in recent versions of WP (update available)

I noticed the plugin wasn’t working on WP 4.9 or 5, and hasn’t been touched in quite a while. If anyone else is continuing to use this plugin, there’s an update available on Github here:

https://github.com/miya0001/child-pages-shortcode/pull/9

I’m trying to get in touch with the author so the official release can be fixed.