Thompsons WaterSeal Advanced has been on the market
for a couple of years. The label promises "Easy soap & water
clean-up," the product apparently reformulated so as to comply
with European Union regulations restricting volatiles.

In practice, soap and water cleanup is by no means "easy."
The product contains some sort of wax that repels water
(and I dare say makes it effective on timber.) But what
sort of solvent can actually dissolve this component
so we can clean our brushes for reuse?
--
Don Phillipson
Carlsbad Springs
(Ottawa, Canada)