Although monthly donations presumably get more siphoned off in processing fees than an equivalently large donation annually.

I dont know if Paypal allows for monthly donations but they dont have any processing fees

https://www.paypal.com/fundraiser/charity/3675786

Good to know!

But your link now leads to a “The charity you're looking for isn't available right now” page?

Interesting, I just clicked that link and it worked for me

Try searching for Signal Tech Foundation here https://www.paypal.com/fundraiser/hub

Ah, PayPal URLs without a country code specified defaults to only showing or returning search results for the country they geolocate you to.

Non-American users can access the Signal PayPal page at Paypal’s US site: https://www.paypal.com/us/fundraiser/charity/3675786

Not sure what the logistics of sending money to the USA PayPal Giving Fund are for non-Americans.