Re: Mozilla and the Shadow DOM

On Wed, Apr 8, 2015 at 8:17 AM, Anne van Kesteren <> 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.


Received on Wednesday, 15 April 2015 13:31:02 UTC