A lot of new features for donation can be find in the following OXP video: https://www.youtube.com/watch?v=kopbe_eQDXI

In short, there is 3 way to do it:

1. If having a price chosen by the customer is not too important, you can always create a "donation" product and set its price.
   
2. Otherwise, there are new blocks in the website, allowing to make donations, be careful it will not create a new product in the cart but an immediate payment: 
   
3. Just create a donation page with the bank information and a form as there is no need to sell a product.