Kraken makes no promises/guarantees/warranties on the outcome of potential or proposed forks, but we will make our best effort to handle things in a way that benefits the most clients. In general, clients should manage their own digital assets if they want to ensure that they have access to funds on all forks. It may therefore be advisable to withdraw affected digital assets in the event of a fork.
Please do not contact our support team to inquire about potential or proposed forks, there is nothing else for us to add than what is above.
If you are wondering specifically about Bitcoin Gold (BTG), please see the following tweet from us: https://twitter.com/krakenfx/status/922605826627342336