
Chrome 53 Beta: Shadow DOM, PaymentRequest, and Android Autoplay - itayadler
http://blog.chromium.org/2016/08/chrome-53-beta-shadow-dom.html
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allendoerfer

        HTTP/0.9 has been deprecated in favor of HTTP/1.0,
        which adds response header support.
    

Wow, I would not like to maintain software that has to support obsolete
standards for another 20 years after they died. But somewhere in a basement a
terribly infested server just got very lonely.

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borplk
Does Shadow DOM have any significance on other things like React? (for example
performance gains or similar?)

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spankalee
The performance gains can be significant. Styles in shadow roots have less
rules, styles lower selectivity than in global styles. The browser takes into
account the shadow scopes when doing style invalidation and recalc, and so
typically recalculates much less of the tree.

Like ebidel mentions, the developer side is important too. You get to write
simpler selectors and know that you aren't accidentally styling other parts of
the document. I'd go so far as to say that Shadow DOM fixes most of the
problems with CSS.

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merb
I wonder when the performance degrades. Consider a angular app which contains
100-200 components (shadow-roots) on a single page.

I mean theoretically it will still be faster since incremental-dom now see's
less Node's for every root, but I thing the memory usage will probably way
higher.

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spankalee
There's the cost of an extra node, since a shadow root is a node. It shouldn't
be too much overall though.

Angular doesn't use incremental-dom, but yes, incremental-dom could walk
smaller subtrees. incremental-dom could also walk smaller subtrees by calling
it on small containers too. That's probably already the common pattern for
componentized users of incremental-dom. I'm not sure why the memory usage
would be much higher.

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merb
angular2 uses it.

I have an additional node. considering I change a upper shadow-root which has
50+ shadow-roots it's 50 more node's.

We have lists which have a component per cell and per row which is like 100x10
lines. That would mean 1000 x 2 node's more? Changing the whole table would
probably be way slower without the inner shadow-root's.

