[This example](https://codesandbox.io/s/1zn2o513pq) presents a huge performance drop between React 16.2 and React 16.3.

In investigated it and noticed several things:

- Perfomance drop is only visible using development bundle
- This is not related to styled-components (a simple div presents the same problem)
- I tried to investigate in performance tab of Chrome dev tools and I noticed that I get React measures even without "?react_perf"
- React Tree Reconciliation seems very long, do not know why

It is not a big problem for me, but it looks weird, so I decided to [share it on Twitter](https://twitter.com/neoziro/status/979756579296817154),  then @gaearon [invited me to submit an issue about it](https://twitter.com/dan_abramov/status/980036013518139398).


return scheduleWorkImpl(fiber, expirationTime, false);
  }
  function scheduleWorkImpl(
    fiber: Fiber,
    expirationTime: ExpirationTime,
    isErrorRecovery: boolean,
  ) {
    recordScheduleUpdate();
    if (__DEV__) {
      if (!isErrorRecovery && fiber.tag === ClassComponent) {
        const instance = fiber.stateNode;
        warnAboutInvalidUpdates(instance);
      }
    }
    let node = fiber;
    while (node !== null) {
      
      
      if (
        node.expirationTime === NoWork ||
        node.expirationTime > expirationTime
      ) {
        node.expirationTime = expirationTime;
      }
      if (node.alternate !== null) {
        if (
          node.alternate.expirationTime === NoWork ||
          node.alternate.expirationTime > expirationTime
        ) {
          node.alternate.expirationTime = expirationTime;