I mostly see folks on here pimping the Mostenbockers lift-off graffiti remover available in spray bottles...but I find their other product that is lesser known has worked way better for me - especially on woodrail legs and rails - it used to be called Lift-Off Gel, but they seem to have removed the GEL word, and now just call it Paint and Varnish Remover. You can tell it's the right product by the spout opening.
It works good on stains too, hence the "varnish" I guess, which is once again very useful in woodrails.
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