[clessg]

Pete Hunt's talk is good. https://youtu.be/x7cQ3mrcKaY?t=1112 I'd recommend watching the entire video if you have time, but that's the gist of it. More detail:

http://stackoverflow.com/questions/21109361/why-is-reacts-co...

It is challenging to make a large app with lots of state be performant when you manually mutate the DOM, and there's no way for the browser to fix that because of the way things work.

For example, if you move an element, and then request the position of another element immediately after, the browser will be forced to recalculate layout before giving you an answer. With lots of state and lots of updates, it's very challenging to keep this in the right order.

As virtual DOM is an abstraction over the DOM, you can make a vanilla app that is much faster, but as your app grows, that quickly reverses.

[jarek-foksa]

Shadow DOM will allow browsers to optimise their rendering code to re-render encapsulated DOM subtrees independently of each other.

Virtual DOM makes sense when (A) you have a huge tree and (B) you show only a small portion of that tree to the user at any given time.

For example a long scrollable list or a multi-line text editor would be better implemented with virtual DOM, but using it everywhere is an overkill.