Standard WP Gallery to use rtmedia lightbox

I’d like my post images to use the rtmedia lightbox.

I’m using a custom post type which is front-end submitted and uses an ACF gallery field.

I found a post from 2013 stating that rtmedia doesn’t support standard WP posts and pages, but your documentation suggests otherwise.

Please can you confirm?

Also, can you confirm if the uploader can be available to the post author only?

Many thanks