This quote from LoyceV could certainly be enough to prove their gender identity
I tried to convince her otherwise, as it's very close to butka and AlcoHoDL, but she's sure about it Cheesy
P.S Why should they confirm their gender and what it has so with their account? If they are a female, will you be rude over them or willing to overpower them? A male dominant mindset is not good!
If one doesn't know the opposite party gender in a public discussion forum, mentioning them as 'they,them,their's' would be appropriate.