There was a live screen-share coding challenge. The question was related to splitting a linked-list. I would recommend practicing online coding puzzles that you may not encounter at work on a regular basis. The coding challenge was about ~25 mins long, so time is an important factor. I think I got pretty far along but I felt I froze at the end and couldn't wrap it up. Being in firmware, I would have expected questions like around volatile, interrupt handlers, mutexes, semaphores, devices drivers, tasks, DMA, serial protocols etc. But perhaps its not important in the first round.
