Adding buttons to admin panel

[harry1]

Hi all

I've done some searching and read through WHMCS Documentation but I can't find the best way to do this.

I'd like to either add some text to an order page or a button on a domain (without editing a registrar module) which when clicked shows a modal with some text. The theme is encrypted so cant do there and I can't find any documentation for adding buttons outside of a registrar module.

Hoping someone can point me in the right direction?

Cheers