Does anyone have any experience running a donation based or a pay-what-you-want side-project? Was it profitable? I am asking because I am working on a small si

Does anyone have any experience running a donation based or a pay-what-you-want side-project? Was it profitable? I am asking because I am working on a small side-project called Email This (https://www.emailthis.me https://www.emailthis.me). I plan to let it run for free, but if someone is interested they can support the app with a donation.