The will-change property hints the browsers what properties are going to change.
Therefore, helping the browser set up optimizations before an element is actually changed.
This is great for optimizing animations / transitions.
Here's how it's done
Although it seems cool to use will-change as much as you can to optimize the performance of the page.
It's recommended to use on elements that are sure to change like sliders, modals.
Moreover, will-change property should only be used to tackle performance issues not anticipate them.
Optimizations use machine resources to accelerate the rendering process and it can become a lot labor intensive for browser to optimize unnecessary elements.