Ask HN: Hackable browsers with file system access?

I need a way to automatically filter out YouTube recommendations that never go away from my home page. In order to do this, if a recommendation hasn't disappeared x number of times it's shown on my home page, I need a place to store the video ID so I'm able to filter it out. I use YouTube in Incognito mode so using localStorage would not work.

I can only really think of a way to do this with some kind of browser that's easily hackable, can inject scripts, and can write data to a local file.

Anyone know of any browsers that can do this?