https://codesandbox.io/s/upbeat-frost-3tt25

1. Press Suspend, see "Loading..."
2. Wait five seconds, you'll see "Happy birthday" at some point 
3. You won't see it again no matter how long you wait

Expected: you'll see it every five seconds.
if (enableProfilerTimer && workInProgress.mode & ProfileMode) {
               
              let treeBaseDuration = 0;
              let hiddenChild = primaryChildFragment.child;
              while (hiddenChild !== null) {
                treeBaseDuration += hiddenChild.treeBaseDuration;
                hiddenChild = hiddenChild.sibling;
              }
              primaryChildFragment.treeBaseDuration = treeBaseDuration;
            }
             
            const fallbackChildFragment = createFiberFromFragment(
              nextFallbackChildren,
              mode,
              renderExpirationTime,
              null,
            );
            fallbackChildFragment.return = workInProgress;
            primaryChildFragment.sibling = fallbackChildFragment;
            fallbackChildFragment.effectTag |= Placement;
            primaryChildFragment.childExpirationTime = NoWork;
            workInProgress.memoizedState = SUSPENDED_MARKER;
            workInProgress.child = primaryChildFragment;
             
             
            return fallbackChildFragment;
          }
        }
      }