They say:
GitHub Pages sites shouldn't be used for sensitive transactions like sending passwords or credit card numbers.
This, even though they officially support HTTPS.
See this scenario: I'm hosting static website on Github, with HTTPS enabled. I have a server running in a cloud, and all the non-static information I gather/display on the static website is stored on/fetched from this server, over HTTPS.
If the static website is behind HTTPS, and all my connections to cloud servers are HTTPS too, then I should be able to use Github Pages for sensitive transactions like sending passwords or credit card numbers, right?
I am curious what's the reason Github says you 'shouldn't do it', although I feel there is a way to be secure while using GitHub pages.