declarative-shadow-dom

This feature was initially proposed by the Chrome team and was first implemented in Chrome about two years ago. See https://github.com/mfreed7/declarative-shadow-dom and https://caniuse.com/declarative-shadow-dom

Take a look at Declarative Shadow DOM: https://github.com/mfreed7/declarative-shadow-dom This is basically the SSR spec for web components.

Hmm, I see that Chromium shipped their implementation a year ago now; I had missed that. Other than that, there’s been no real change in the situation in the last almost two years (since Shoelace 2.0 was released, the last time I examined the situation). And there still doesn’t look to be any real interest in actually implementing it outside of Google: Mozilla are unenthusiastic though not against it <https://mozilla.github.io/standards-positions/#declarative-s...>, and WebKit still find fault with some aspects of the design (https://lists.webkit.org/pipermail/webkit-dev/2021-February/..., https://github.com/mfreed7/declarative-shadow-dom/issues/9), though they’re content most of the earlier issues (especially performance) are ironed out. So you certainly can’t rely on scriptless server-side rendering of Shadow DOM being possible—it’ll wo

Work is underway on speccing out declarative shadow doms, which would remove the need for that JS: https://github.com/mfreed7/declarative-shadow-dom

To play devil's advocate, note that Google is trying to propose something to make the shadow root contents deserializable without relying on JavaScript [1][2]. [1] https://github.com/mfreed7/declarative-shadow-dom/blob/maste... [2] https://groups.google.com/a/chromium.org/forum/#!msg/blink-d...