Sharing my interview experience here for the Atlassian Principal Frontend Engineer (P60).

Location: Bangalore, India

1st Round UI Coding:
Build a Tab component with some variations like lazy loading content when Tab Panel is visible.

2nd Round JS Coding:
Build a function to measure performance of a given function(s). I tried to use Date.now and later realised about using Performance.now group of functions. Hint: Run functions multiple time to get average running time. Also handle Sync and Async functions.

3rd Round System Design: Design Google Editor. There was more focus on Conflict resolution algorithms (OT and CRDT) and the edge cases.

Result: Rejected. Bombed 3rd round as probably didn't had good understanding about OT and CRDT algorithms.

Other interview experiences:
New Relic - Lead Frontend Engineer (Reject)
SurveyMonkey - Staff Frontend Engineer ( Reject )