I don't know if it's just me, but this script hasn't worked on my machines for quite a while, and I'm not aware of an alternative. I forgot all about it until just earlier today, and since I remember it being useful, I decided to get it working again.
I didn't make the original script, so I hope the author doesn't mind.
I also made a couple of minor improvements, like reading which boards the user jannies from local storage, so the buttons won't appear on every board like they (probably) did in the original.
I don't do a lot of JS, so while it's working on my machine, it might not work properly for you.

https://cryptobin.co/c1a5y357
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