Got contacted by a recruiter and did a Hackerrank challenge (same Grid Illumination question as several other people seem to have gotten). Did poorly on it but got contacted about a week later for a 1 hour phone interview. Several days after that, got an email from my recruiter to schedule an onsite interview which consisted of three, 1 hour interviews, lunch, and a product demo. I'll note that among these interview questions (phone + onsite), I did get a couple that others shared on Glassdoor, which I've included below. Overall, the interview process was very smooth and enjoyable, though the questions I was asked were by far the hardest that I encountered this recruiting season (harder than Google, Facebook, etc.). My recruiter was incredibly prompt and accommodating and really seemed to care about the candidates they were working with. Also all the engineers I met were super on top of their interviewing game and were very friendly and knowledgeable, and seemed to really enjoy working at Dropbox.

Process was 2 online assessments, followed by a phone screen and then final. Final was 3 round. 1 coding challenge, a code review and behavioral. Interviewers were friendly and cooperative. Recruiting process was very slow. Took about 2 months to get to final.