[lucb1e]

I don't know what the requirements are, maybe you need to be open source non profit something, but by far the easiest-to-use alternative I've seen is

https://liberapay.com/ (imagine your bank or paypal were open source: https://github.com/liberapay/liberapay.com )

I am not affiliated in any way, but I funded K9 mail through this, F-Droid, Matrixdotorg, and presumably more projects in the future. It's so pain-free, just put in any amount, your details (IBAN, address), check the box to authorize the direct debit, done. No account needed, but you can check your history by "logging in" which just emails you a one-time login link.

It's also transparent about how much the beneficiary is already receiving, so it doesn't feel like you're all dumping money into a black hole with no idea if it's way too little or already a decent amount (and you can fund other things instead). I just wish more projects used it.

[rexreed]

LiberaPay uses paypal and stripe: "What payment methods are available? The available payment methods depend on which payment processors are supported by the recipient. If a payment is processed by Stripe, then most credit and debit cards (Visa, MasterCard, American Express) are accepted, as well as SEPA Direct Debits (for Euro donations only). If a payment is through PayPal, then it's possible to pay in various ways, however the donor needs to have or create a PayPal account."

[lucb1e]

Ah, then I guess I'm the fortunate European here. Too bad they don't have an equivalently great option for non-Eurozone.