privacy-redirector/doc/TODO.md

I know that some of the Invidious instances are faulty, I'm going to fix it in a month along with all the to-dos below.

To-do

• Use pathname.startsWith instead of href.indexOf
• Fix: Medium stops redirecting to scribe.rip after entering a user page

Not possible (?)

• Make the previous site after redirecting is the original previous site and not the platform itself.