React 18: useEffect different behaviour compare to v17 in specific cases

<!-- Ask a question or share feedback about the React 18 release here. --> Hi! In [this](https://github.com/tannerlinsley/react-query/issues/2628) issue to react-query repo we found some strange useEffect behaviour. Here's examples: [react 17](https://codesandbox.io/s/react-or-react-query-bug-version-2-forked-fnebv?file=/src/example.js) [react 18 with old root api](https://codesandbox.io/s/react-bug-version-3-x8fs6?file=/src/example.js) Just click "rerender" button and see that there's no effect firing. But in react 18 with the new root API it works fine: [codesandbox](https://codesandbox.io/s/react-bug-version-3-forked-8mxy2?file=/src/example.js) I tried to explain it like that: > So, in our case we have `dummy` and `forceRerender` state variables. After calling `rerender` function, `dummy` updates with the same value, and React bails out without rendering the children or firing effects. I suppose that somewhere here the effect should've been scheduled, but it didn't because of that react behaviour. BUT, the render function was actually called and useEffect received updated `value` in deps (you can see this by checking how many times console.log was called in render). And then on the next tick `forceRerender` causes another update, but this time it doesn't schedule the effect because it has the same deps (`value`) that were captured in the previous render function call. So, is this right explanation for what is going on there? And I guess, the main question, why does this example work fine when the new root api is used? Does it mean that with the new root api (and with concurrent mode) useEffect compare deps only with those from the last previous render that was committed to the DOM? Thanks!