diff --git a/polygerrit-ui/app/elements/change/gr-thread-list/gr-thread-list.ts b/polygerrit-ui/app/elements/change/gr-thread-list/gr-thread-list.ts
index e236652..ff30452 100644
--- a/polygerrit-ui/app/elements/change/gr-thread-list/gr-thread-list.ts
+++ b/polygerrit-ui/app/elements/change/gr-thread-list/gr-thread-list.ts
@@ -159,7 +159,9 @@
     if (c1.thread.patchNum !== c2.thread.patchNum) {
       if (!c1.thread.patchNum) return 1;
       if (!c2.thread.patchNum) return -1;
-      // TODO(TS): Explicit comparison for 'edit' and 'PARENT' missing?
+      // Threads left on Base when comparing Base vs X have patchNum = X
+      // and CommentSide = PARENT
+      // Threads left on 'edit' have patchNum set as latestPatchNum
       return c1.thread.patchNum > c2.thread.patchNum ? -1 : 1;
     }