Will a visa or mastercard gift card work for donating?
They should. I don't see any reason why they wouldn't.
Okay thanks. Just wanted to double check.
Yup, I'm pretty certain they do. I've heard of multiple other people that have done so, it's actually one of the methods I recommend for people who don't have a card or active paypal account of their own.
Those credit card gift cards work exactly like a normal credit card does. Same process, it's just preloaded with money. So yes, anywhere you can use a credit card you can use one of those credit card gift cards. Paypal allows you to pay with credit card... and you don't even need to sign up for an account. There shold be a pay by credit card link hiding in the lower corner somewhere.