Skip checkpoint redirects

[acjbrouwer]

New Issue Checklist (tick off like this: [x])

• [ ] I checked existing issues (open and closed) for possible duplicates
• [ ] I can reproduce the problem on the latest stable version (not nightly!)
• [x] If you have a problem with a specific website: adding the domain to your no-skip-urls-list does not solve the problem
• [ ] The issue is not about adding entries to the default no-skip-urls-list

What is your browser?

• [x] Firefox
• [ ] Chrome

What is your operating system?

• [ ] Linux
• [ ] Mac
• [x] Windows

Description (please include examples/screenshots where applicable)

The following redirect is currently not skipped: https://protect.checkpoint.com/v2/___https://discourse.jupyter.org/t/how-to-set-secure-cookie-and-httponly-flag-in-z2jh/25744___.YzJlOmlpYXNhOmM6bzozMGFmMzNiMDdiYjM2ZTJkNDlkZDE2ZjZkOGY0NDYxYjo2OjU2NjA6ZDY4NGY5NDAyNDYzODlhOGVlMjQ2YmQ3NjE3MTU0ODRkZWI0NDE1YTc0ZTRmNTRjZTIzMWNkOTQ0MjVkNWMyNTpoOlQ

Please support skipping to the URL bracketed in triple underscores.

[sblask]

This is a bit too specific for my taste. They could decide to change the format at any time, like use more or less underscores. That is not something I want to Maintain.