Until now web developers have been advised to use only transform & opacity CSS properties for smooth and performant animations, as they are hardware-accelerated by the GPU. Animations using other CSS properties are not hardware-accelerated, hence are not guaranteed to be smooth.
Google Chrome now plans to add background-color & clip-path to the list of animatable CSS properties which are hardware-accelerated by the GPU. This will happen in a future version.
This is a good news for developers who have been mainly stuck with transform & opacity to perform animations. With background-color & clip-path coming up, their options will increase.
background-color is a priority as they seem to be highly implemented by websites. clip-path on the other hand enables more performant transition effects.