I think I wrote my own Javascript in the console to do this, thinking about it, but the basic idea is https://gist.github.com/renestalder/c5b77635bfbec8f94d28 h

I think I wrote my own Javascript in the console to do this, thinking about it, but the basic idea is https://gist.github.com/renestalder/c5b77635bfbec8f94d28 https://gist.github.com/renestalder/c5b77635bfbec8f94d28 (I've not run this so do check it before doing so)