I have my BTC in my trezor wallet (had it for a while before the BTG fork), now I would like to send some BTC to Bitfinex, but I am worried that if I do so, it will also send my BTG to the same address on Bitfinex and so losing my BTG. Can anyone tell me if my assumption is correct ? Thanks
As of right now (October 25), the Bitcoin Gold fork is not yet finished, despite being already forked, and nobody is still sure how it will work.
So it might indeed get replayed on the Bitcoin Gold chain, but it also might not. If you want to be sure, you cannot send Bitcoin to other people's addresses until Bitcoin Gold is live.
In my opinion, Bitcoin Gold is not worth it, but that's up to you.
until the BTG fork is complete, sending bitcoin to a 3rd party might risk your access to BTG.
that said, sending anything to bitfinex might be a risk in itself, given that there is accusations public that bitfinex has no bank accounts and may be involved in multiple accounts of fraud.
always do your due diligence. never trust random strangers (me included).