Intent to ship: scrollbar-color and scrollbar-width properties

[Xidorn Quan]

As of Firefox 64, I intend to turn scrollbar-color and scrollbar-width properties on by default on all platforms. They have been developed behind pref "layout.css.scrollbar-colors.enabled" and "layout.css.scrollbar-width.enabled" respectively.

Other UAs don't currently have plan to ship it, but WebKit and Blink have non-standard -webkit-prefixed scrollbar pseudo-elements support for long, which the CSSWG agrees that it is not something should be kept on the web platform, while Gecko has been facing some compat pressure for this. These two properties should cover most of the common use cases, and we can use them to convince websites to support Firefox, as well as shipping our own fixup stylesheets with Go Faster when necessary.

Bug to turn on by default: https://bugzilla.mozilla.org/show_bug.cgi?id=1492012

The features were previously discussed in these "intent to implement" threads:
* scrollbar-color: https://groups.google.com/d/msg/mozilla.dev.platform/X_tv4aH4NxQ/w497k6J7CQAJ
* scrollbar-width: https://groups.google.com/d/msg/mozilla.dev.platform/JhdWiVwgQeo/tSKKqatvCQAJ

Note: scrollbar-color was initially two separate properties. It has since be merged into a single property because the two colors are serving a single use case, and it doesn't make much sense to use them separately. This change also resolves the concern over what should happen when one color property is specified while the other is not, which was raised in the "intent to implement" thread.

- Xidorn

[Tantek Çelik]

On Tue, Sep 25, 2018 at 5:59 PM, Xidorn Quan <m...@upsuper.org> wrote:
> As of Firefox 64, I intend to turn scrollbar-color and scrollbar-width properties on by default on all platforms. They have been developed behind pref "layout.css.scrollbar-colors.enabled" and "layout.css.scrollbar-width.enabled" respectively.

Great work Xidorn!!!

Also as of *today* the W3C has published the first public working
draft of CSS Scrollbars Module Level 1 which defines these properties:

https://www.w3.org/TR/css-scrollbars-1/

> Other UAs don't currently have plan to ship it,

They don't have explicit plans, however at least two have strongly
indicated they would like to in past CSSWG f2f meetings. I think we
can affect that by shipping. We will bring this up at TPAC.

> but WebKit and Blink have non-standard -webkit-prefixed scrollbar pseudo-elements support for long,

And they have also indicated they want something better (simpler,
easier to maintain) to recommend for the future. The current design
incorporates a bunch of the feedback from WebKit and Blink when these
features were discussed in the CSS Working Group.

> which the CSSWG agrees that it is not something should be kept on the web platform, while Gecko has been facing some compat pressure for this. These two properties should cover most of the common use cases, and we can use them to convince websites to support Firefox, as well as shipping our own fixup stylesheets with Go Faster when necessary.
>
> Bug to turn on by default: https://bugzilla.mozilla.org/show_bug.cgi?id=1492012
>
> The features were previously discussed in these "intent to implement" threads:
> * scrollbar-color: https://groups.google.com/d/msg/mozilla.dev.platform/X_tv4aH4NxQ/w497k6J7CQAJ
> * scrollbar-width: https://groups.google.com/d/msg/mozilla.dev.platform/JhdWiVwgQeo/tSKKqatvCQAJ
>
> Note: scrollbar-color was initially two separate properties. It has since be merged into a single property because the two colors are serving a single use case, and it doesn't make much sense to use them separately. This change also resolves the concern over what should happen when one color property is specified while the other is not, which was raised in the "intent to implement" thread.

The features have definitely benefited from public iteration.

Thanks again,

Tantek

[Jonathan Kew]

On 26/09/2018 01:59, Xidorn Quan wrote:
> As of Firefox 64, I intend to turn scrollbar-color and scrollbar-width properties on by default on all platforms. They have been developed behind pref "layout.css.scrollbar-colors.enabled" and "layout.css.scrollbar-width.enabled" respectively.

Awesome, thanks for this work!

One tiny nit, which may not be worth bothering about at this point: it
seems slightly unfortunate that the pref is
"layout.css.scrollbar-colors.enabled" (plural) when the property name is
"scrollbar-color" (singular).

I realize this originated back when there were two scrollbar-*-color
properties, so using plural for the pref made sense, but now it just
feels a bit confusing.

Maybe consider dropping the final "s" from the pref name so it better
matches the feature it controls?

JK

[Xidorn Quan]

Sounds reasonable. Fixing in https://bugzilla.mozilla.org/show_bug.cgi?id=1494501

I initially thought it's probably not worth bothering... but it's indeed better if they match each other.

Thanks.

- Xidorn