Bug: The top navigation bar disappears – Quip - Docs, Chat, Sheets Review

Steps to reproduce: 1. Directory and files structure: - a/b/doc1 - a/b/doc2 2. Open doc1 in updates tab 3. Open directory b from the top navigation bar 4. Open doc2 in directory b 5. Click back on top left, back to dir b, then click and back again to doc1 6. You will get the bug: the top navigation bar disappeared, you can't go anywhere now, except kill and reopen the app.
Review by ZHUO.QL on Quip - Docs, Chat, Sheets.