No, I had a paper gasket in there originally, but it just seemed to dissolve, then I tried some 'instant gasket' stuff only because I had nothing else to hand. That's held for a few weeks, but now started leaking so I bought a Cometic gasket.
Never used one before, and they seem to be a layer of metal sandwiched between a couple of layers of a foamy, rubbery sort of material.
Didn't know whether anyone used additional sealant so just asked the question.
Fitted now (without sealant), and seems to be ok at the moment