Hey @sreeman -
You will definitely want to use the custom domain when registering with Remarkbox, but in fact you may register both, each will have it's own owner id so they will be treated as separate websites (for example, you could do your comment testing on the
github.io domain before transitioning to the production domain)
I've never used Github pages before but it seems like it may host static web sites so any page you put the snippet will have the comment page appear. Depending on how you are building your web site's static pages will depend on if you may automatically add comments to a blog post article for example.
If you have a repository which I may look at I might be able to offer specific guidance on your HTML or static site generator.
Reach out here if you need more specific help: https://russell.ballestrini.net/contact/
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