Fwd: Prohibiting authors from disabling Pinch Zoom as failure for Reflow 1.4.10

Forwarding a question from Josh on the main working group list that I'd
like to expand on, given the conversation we had around conformance and
user agent requirements.

Flipping the question of how to express usability failure in terms of user
agent / assistive tech / platform gaps around to the other case: currently,
Chrome (Android) offers a setting to enable the user to remove the ability
of a site to disable pinch zoom (Settings > Accessibility > Force enable
zoom), but Chrome for iOS doesn't offer this (that I can find, at least).
If I use a user agent that ensures I can zoom no matter what the content
specifies, implying other user agents could very well offer the same
feature, does this still constitute a failure? Does that failure's
responsibility sit with the user agent or the CSS of the site?

Given our current direction of only having methods and not having "Failure
techniques", I think this example would pass, as the user has ways to still
zoom as needed, given that a cognitive walkthrough would take into account
the user agent ability to override the zoom behavior of the site (just like
user stylesheets can override site CSS).

What do you think?

-Shawn

On Tue, Jan 29, 2019 at 9:26 AM Joshue O Connor - InterAccess <
josh@interaccess.ie> wrote:

> Hi,
>
> In the failures section there are 'draft' failures listed. This one with
> health warnings.
>
>
>    - @@ "Interfering with a user agent's ability to zoom" i.e., author
>    using: maximum-scale or minimum-scale or user-scalable=no or
>    user-scalable=0 in the meta element ?? @@ Note: In Pinch zoom thread
>    on the WCAG list
>    <https://lists.w3.org/Archives/Public/w3c-wai-gl/2016AprJun/0502.html> people
>    did not seem to be in favor of this as a failure.
>
>
> While it would make a tidy failure if we could say - 'do not disable pinch
> zoom'. If that's not a runner it should be removed as a failure as its
> currently confusing to see it there. I see Jon and Patricks comments after
> David posed the question.
>
> Any good reason for keeping it?
>
> Thanks
> --
> Joshue O Connor
> Director | InterAccess.ie
>