Was asked to do a case study before interviewing. I did so and sent them my work. Received a response saying that one of the points I raised was a critical issue on their website, and was asked to send them a video of me recreating the issue so they could fix it. I did so because I thought it would help with my application. I received no response to this extra work I did. I chased them 2 weeks later asking about my application, only to receive a response saying that their initial email must not have reached me and that they had picked another candidate quickly because the candidate had another offer. No recognition for going above and beyond, and very little acknowledgement that I did lots of free work for them.