It seems similar to the Boost and Membership banners, but as far as I can tell, the “Buy Me A Coffee” banner is only available for MakerLab generators and can’t be added to regular model descriptions.
I think this would be a great feature to make available to model creators as well. Having a dedicated banner directly in model descriptions would greatly improve the visibility of tipping as a way to support creators, rather than relying on users to find a creator’s profile or external support links. It would make it much easier for users who enjoyed a model to leave a small tip and directly support the person who made it
You will see the Header and Footer that will be added to all your models when you publish them.
I put an image from “Buy me a coffee” there and linked it to my bmac account.
I have a Ko-fi button that I use similarly. However, this button that the OP has found is a different beast. It’s similar to boost and commercial membership widgets with the button being separate from the background image and text. It’s very slick and official looking. No idea if it’s an actual MW widget or a cleverly disguised bit of custom inline script. Either way, I’d love to be able to use it myself.