tldr; After hours of interviews and exercises they ghost and give no feedback. I managed to complete Canonical's "early stage" interviews - 4 one hour interviews and 4 exercises (1 written, 2 psychometric, and a coding exercise). Although I had great conversations and loved meeting everyone (best part), Canonical ghosted for 2 weeks despite reaching out to my hiring manager for any updates. When they did respond, it was the most generic email: "We are writing to let you know that we have reviewed your application. We regret to inform you that we shall not be progressing your application further for this particular role". Given the progress through the process I would've expected some correspondence or feedback, but they just send an inpersonal email. If they provided ANY kind of feedback that would definitely get rid of the question marks. Instead, Canonical conveys that they do not care about you or the time you spent in their overly long process, even if you do make it to the further rounds.

Long introduction. They ask to include grade ot graduation and high school and copy of you diploma. Copy of a diploma is something companies request after the offer. Don't waste your time with this company.