I saw some people got ghosted after the interview and I experienced similar situation. Don't think it's great for them to ghost candidates for 2-3 weeks after candidates have submitted a take home assessment on time. Alot of rounds and the waiting time between each round to hear back is super long. I don't think that the process should be this long for support engineer tbh. For questions, just learn about company and then check out their products, their graphs, etc and you'll be alright. Mostly vibe check tbh

Position turned out to be Level 1 Support Engineer. Applied online and was contacted by Recruiter. First phase was an online "Take Home Assignment" where you were tasked with answering an example of an emailed customer question. Assignment was timed at 30 minutes. It wasn't too difficult to figure out by just looking at the question and image, but reviewing their documentation first would certainly help, Next was a 30 minute typical recruiter phone screening. I made it to the next round which was a 60 minute interview with a Level 3 Support Engineer. There were a series of behavioral questions along with a technical question which required the calculation of conversion rate from a series of values. At the end of the interview, an example support question was verbally relayed with values and the request was to think about the issue and reply via email (address also given on the call) to the interviewer with the answer as if they were a customer. The clear intent was to determine if you were able to take good notes about the issue and reply with a clear summary of the situation and recommendation to the customer. (Not to mention get the email address correct.) I did not make it to the next round and the "After careful consideration" message was delivered via email.