See 'Help donating with another currency or payment method' at https://www.thunderbird.net/en-US/donate/help/.

https://www.thunderbird.net/en-US/donate/#faq

What are the ways I can give? You can donate online securely by credit card or PayPal, Google Pay, Apple Pay, and by bank transfers through SEPA, iDEAL and ACH. Give in your local currency! We accept over 100! Choose yours from the drop down menu next to ‘Amount’.

I send paper checks.

You can give offline in USD only by mailing a check or money order made payable to "MZLA Technologies Corp". Mail to:

   MZLA
   PO Box 25718
   Pasadena CA 91185-5718