An app that checks how batching works in React 18.2. The app Uses two states variables: a counter that is incremented, and a flag that is toggled between 0 and 1. A button when it is clicked, the states are updated, and the GIF below shows how many times a re-render takes place.
Then, the states are updated inside a timeout, and the GIF below shows how many re-renders take place.
We notice that in the very first state updates, the re-render takes place twice, this is due to the fact that we are using Strict Mode, and in the next state updates, it will be batched and takes place only once.