Intent to Implement/Ship: -webkit-text-stroke

[Jeremy Chen]

*Summary*: We don't currently support -webkit-text-stroke; however, it has
been available for years in webkit based browsers and has seen widespread
usage on the web. This css property is currently available in Chrome and
Safari.

*Bug*: https://bugzilla.mozilla.org/show_bug.cgi?id=1248708

*Link to standard*:
https://compat.spec.whatwg.org/#text-fill-and-stroking

*Platform coverage*: All platforms.

*Estimated or target release*: Firefox 48

Preference behind which this will be implemented:
layout.css.prefixes.webkit

Cheers,
Jeremy Chen
Software Engineer, Mozilla Corporation
Tel: +886-2-8786-1100 #285
E-mail: jerem...@mozilla.com

[Jeremy Chen]

[Ms2ger]

On 14/04/16 09:26, Jeremy Chen wrote:
> *Summary*: We don't currently support -webkit-text-stroke; however, it has
> been available for years in webkit based browsers and has seen widespread
> usage on the web. This css property is currently available in Chrome and
> Safari.

How about Edge?

Should we implement an unprefixed version as well?

> Preference behind which this will be implemented:
> layout.css.prefixes.webkit

Should this have a more specific pref?

Thanks
Ms2ger

[Xidorn Quan]

On Thu, Apr 14, 2016 at 7:40 PM, Ms2ger <Ms2...@gmail.com> wrote:

> On 14/04/16 09:26, Jeremy Chen wrote:
> > *Summary*: We don't currently support -webkit-text-stroke; however, it
> has
> > been available for years in webkit based browsers and has seen widespread
> > usage on the web. This css property is currently available in Chrome and
> > Safari.
>
> How about Edge?
>

Edge doesn't support this as far as I can see.

> Should we implement an unprefixed version as well?
>

We don't have a spec in CSS WG yet.

> > Preference behind which this will be implemented:
> > layout.css.prefixes.webkit
>
> Should this have a more specific pref?
>

Why do you think this needs a more specific pref?

- Xidorn

[Daniel Holbert]

On 04/14/2016 02:40 AM, Ms2ger wrote:
>> Preference behind which this will be implemented:
>> layout.css.prefixes.webkit
>
> Should this have a more specific pref?

Absent a compelling reason, no -- it should not.

We're using layout.css.prefixes.webkit here because, without this
-webkit-text-stroke feature, our webkit-prefix support breaks sites.
So, we can't really ship -webkit prefix support without also shipping
support for this feature. And the fewer prefs we have to keep track of
(and to have to worry about enabling/disabling if & when we discover
trouble at the last minute), the better.

Specifically, the dependency is as follows:
(1) The web depends on "-webkit-linear-gradient" as a background.

(2) *But*, it turns out that one common use-case for
-webkit-linear-gradient is to create a background *which is only
intended to be viewed through transparent text*. Some sites (bloomberg
news at least) use "-webkit-text-stroke" as part of this effect.

(3) If we enable layout.css.prefixes.webkit without enabling this one
feature (-webkit-text-stroke), Bloomberg's pull-quotes are unreadable.
Screenshot of what that would look like (taken in Chrome, with the
-webkit-text-stroke declaration manually disabled via devtools):
https://bug1248644.bmoattachments.org/attachment.cgi?id=8719912

(It's a bit more complicated than this; see discussion on
https://bugzilla.mozilla.org/show_bug.cgi?id=1248644 for more details.)

SO: there isn't any graceful fallback if we selectively shipped other
webkit prefixing support without *also* shipping support for this
feature, as shown by the screenshot above. So, it makes sense to combine
it under the umbrella of the same pref.

~Daniel