1486964 - Drop -moz-touch-enabled

Status: RESOLVED FIXED

(Core :: CSS Parsing and Computation, enhancement, P3)

Description

[Hiroyuki Ikezoe (:hiro)]

It can be replaced by 'any-hover: hover' (or hover:hover)?

Comment 1

[jscher2000]

Attachment: Three tests used by Modernizr for touch event support

Modernizr 3.7.1 (March 14, 2019) includes detection for window.TouchEvent, so the legacy detection --

window.matchMedia('(-moz-touch-enabled)');

-- will someday be unnecessary on desktop (I think it's already unnecessary on mobile). However, I'm sure a lot of sites do not update Modernizr very quickly, so this will still be around for a while.

With that in mind:

If the user sets

dom.w3c_touch_events.enabled = 0

to disable touch events, unfortunately window.matchMedia('(-moz-touch-enabled)') still returns true.

This leads to a broken experience on sites where mouse support is disabled in favor of touch support. It also creates a discrepancy that can be used for fingerprinting. How can this be fixed if this media query is going to live on for a while?

Comment 2

[Emilio Cobos Álvarez (:emilio)]

Ideally Modernizr would be fixed. But the media query is gone in bug 1588737.

Comment 3

[Kohei Yoshino]

Well, this bug is for removal and Bug 1588737 is for deprecation...

Comment 4

[Emilio Cobos Álvarez (:emilio)]

Guess we can keep this open and use this bug to flip the pref in release builds.

Comment 5

[Mathew Hodson]

This should block bug 775235 for tracking.

Comment 6

[Emilio Cobos Álvarez (:emilio)]

Yup, it's about time to toggle the pref on in release too.

Comment 7

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1486964 - Disable -moz-touch-enabled in all channels. r=#style,hiro

We've had it disabled on Nightly with no fallout for a while, and having it
enabled breaks websites with touch screens as described in this bug and related
ones.

Given the above, let's disable it in all channels, and we'll remove the code in
the next cycle.

Comment 8

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/8d30b15ca8f9
Disable -moz-touch-enabled in all channels. r=hiro

Comment 9

[Cristina Coroiu [:ccoroiu]]

https://hg.mozilla.org/mozilla-central/rev/8d30b15ca8f9

Comment 10

[Kohei Yoshino]

Posted site compatibility note: https://www.fxsitecompat.dev/en-CA/docs/2019/moz-touch-enabled-media-feature-has-been-removed/

Comment 11

[j.j.]

https://developer.mozilla.org/en-US/docs/Web/CSS/@media/-moz-touch-enabled

could/should have some words and a link to it's replacement media (pointer:coarse)

https://developer.mozilla.org/en-US/docs/Web/CSS/@media/pointer

Comment 12

[Janet Swisher]

Added a warning on the -moz-touch-enabled page that is unsupported as of 73, and to use pointer: coarse (linked) instead.