[quote=@tsukune]but ultimately English is not my native tongue[/quote]

I'd never have noticed, so, as somebody who is trying to achieve fluency in a couple of extra non-English languages (French, German, and Dutch), I'm frankly jealous of your proficiency. :P

That said, most people here are, I think, American, who certainly speak at least a variant of English with different colloquialisms and slang to British English so it typically doesn't help British English speakers either. Consequently, for American settings I tend to find some excuse to play an immigrant (so I don't have to worry about my character using American English) or, in my games (which I would typically set in the UK for my own ease), try to find some convoluted way to enable people to play characters of their own nationality so that no American accidentally tries to play a Brit and refers to a sidewalk, cookies, (non-under)pants without realising. That thing would really piss me off. Nothing against the players that would make those mistakes, but I think it really shatters at least my suspension of disbelief, so I try to find a way around it. This is normally so convoluted as to be restrictive or at the very least left-field - but is better than the alternative.