[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).


if (root.nextScheduledRoot === null) {
      
      root.remainingExpirationTime = expirationTime;
      if (lastScheduledRoot === null) {
        firstScheduledRoot = lastScheduledRoot = root;
        root.nextScheduledRoot = root;
      } else {
        lastScheduledRoot.nextScheduledRoot = root;
        lastScheduledRoot = root;
        lastScheduledRoot.nextScheduledRoot = firstScheduledRoot;
      }
    } else {
      
      const remainingExpirationTime = root.remainingExpirationTime;
      if (
        remainingExpirationTime === NoWork ||
        expirationTime < remainingExpirationTime
      ) {
        
        root.remainingExpirationTime = expirationTime;
      }
    }
  }
  function findHighestPriorityRoot() {
    let highestPriorityWork = NoWork;
    let highestPriorityRoot = null;
    if (lastScheduledRoot !== null) {
      let previousScheduledRoot = lastScheduledRoot;