I'm not 100% sure if this is the relevant place to ask, but any help to point me in the right direction would be greatly appreciated.
I'm using WooCommerce 3.5, and when someone buys a product on my site, they are required to register and supply their billing address, username and password. For all of the users that are registered on my site, there are several other fields in their profile that can get filled in, like website, twitter ID, Facebook, AIM, etc.
If I wanted to for instance require someone to supply their Twitter ID to sign up, how would I go about doing this? Any help is greatly appreciated.