I have been running an open source MathJax-based mathematics pastebin[1] since 2012 and I had received 2 donations for it until recently. Then a mathematician tweeted[2] about it convincing others to send some donations. After that kind gesture by him, I received 3 more donations. So pretty sure I can't make a living out of donations. :-) But I still appreciate them because they help in covering a portion of the hosting cost.
Also, I never seriously expected donations for this project because I don't work much on it these days apart from cleaning up spam from time to time, complying with legal notices and occasional maintenance. I added a donation button only to see if someone would use it. Apart from covering hosting cost, I think an important side effect of the donations is that it provides some additional motivation to continue working on the project and develop it further which I indeed plan to do as soon as I can find the time for it.
Also, I never seriously expected donations for this project because I don't work much on it these days apart from cleaning up spam from time to time, complying with legal notices and occasional maintenance. I added a donation button only to see if someone would use it. Apart from covering hosting cost, I think an important side effect of the donations is that it provides some additional motivation to continue working on the project and develop it further which I indeed plan to do as soon as I can find the time for it.
[1] http://mathb.in/
[2] https://twitter.com/daveinstpaul/status/1345082256361193473