App:a legacy discussion that doesn't allow threading

Build 6437 on ab/refactor-comment-state
1200px
Reviewing disabled
The baseline is taller than the new snapshot (1200x321 to 1200x206).
Baseline History
Build 6437d93bcf7
Current build. There are unaccepted changes, so build 6391 is still the baseline.
Build 63919ce985a current baseline
Accepted by Anna Beddow.
Build 5728fd4f18e
Accepted by Sophie.
Build 5634851d814
Accepted by Sophie.
Build 4536efdeada
Accepted by Sophie.
Commenting is disabled because there's a newer build on this branch