First screen was with a recruiter who gave me the details of a coding challenge, which was a take home project to make a simple web app. I spent a couple of days working on it, and submitted it. Waited a week, and received an automated rejection email with no feedback on my submission. It felt highly unprofessional to expect the candidate to put time into a project but give no feedback on it.

Generic email with generic coding challenge. Attached a pdf with a coding submission, and was given two weeks. Way too much to ask for (these problems should be timeboxed to 3-4 hours MAX). Spent about 6-8 hours considering they wanted unit testing and READMEs etc. No feedback as others have reported here. Zero effort investment by the company, and large time investment expected from candidates. Don't waste your time.