On Wed, Apr 8, 2015 at 8:17 AM, Anne van Kesteren <ann...@annevk.nl> wrote: > * Multiple shadow roots. We'd like to retain this feature. > Although it has complexity, we've heard from both Firefox UI and > Firefox OS application developers that the moment your library gets > sophisticated, you want this for extensibility.
I was asked to provide a use case for our stance. One that we've found with Firefox OS is custom dialogs, quoting Wilson Page: # I have an <x-dialog> component. It takes care of transitioning # in and out of the viewport and appropriate styling contained # elements (<h1>, <button>, <p>). # # I want to be able to extend this component to produce # <x-dialog-alert>. In this case extending the prototype alone # isn't enough, I need to also be able to extend the markup # and styling of <x-dialog>. # # At the point of creation <x-dialog-alert> can add a second # ShadowRoot that allows it to compose its own content # inside that of the 'old' <x-dialog> ShadowRoot. Without this # <x-dialog-alert> would have to duplicate all the markup, style # and interaction code again. -- https://annevankesteren.nl/