1370512 - TouchDisplay not detected

Status: UNCONFIRMED

(Core :: DOM: Events, defect, P3)

Description

[jochen.zink]

Attachment: about_config.png

User Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:53.0) Gecko/20100101 Firefox/53.0
Build ID: 20170518000419

Steps to reproduce:

- Using Firefox on a Windows 10 notebook (HP SPECTRE x360 15) with a touchenabled display
- Trying to detect if the Browser/Device supports touchevents using one of the following methods with JavaScript:
'ontouchstart' in window
document.createEvent('TouchEvent')

The about:config value dom.w3c_touch_events.enabled is set to default value 2 (autodetect). If the key is set to 1 (true) the API works like expected.

One more info: the about:config value "ui.osk.debug.keyboardDisplayReason". has the value "IKPOS: Touch screen not found."

Issue found in 53.0.3 (32bit)
Was also reproducable in beta 54.0b13


Actual results:

'ontouchstart' in window returns false

document.createEvent('TouchEvent') throws an NotSupportedError: Operation is not supported


Expected results:

'ontouchstart' in window returns true

document.createEvent('TouchEvent') works

Comment 1

[Andrew Overholt [:overholt]]

Stone would know what is expected here.

Comment 2

[Kohei]

Dup of Bug 1356695?

Comment 3

[jochen.zink]

Was this fixed in 54.0b13? I tested also this browser and the result was she same.

Comment 4

[jochen.zink]

The info from (https://developer.mozilla.org/en-US/docs/Web/API/Touch_events#Firefox_touch_events_and_multiprocess_(e10s)) with the multi process ist set to 1/1 (active) on the notebook.

Comment 5

[Ming-Chou Shih [:stone]]

Tested with 55.0a1 (2017-06-11) and 53.0.2 (32-bit) on Lenovo YOGA 900(Win10)
'ontouchstart' in window returns true
document.createEvent('TouchEvent') works

Have to find an HP notebook to find the cause.

Comment 6

[Hsin-Yi Tsai (she/her) [:hsinyi]]

Could this be related to whether APZ is supported or not? I was thinking about comment 2.

Comment 7

[Ming-Chou Shih [:stone]]

(In reply to Hsin-Yi Tsai (55 Regression Engineering support) [:hsinyi] from comment #6)
> Could this be related to whether APZ is supported or not? I was thinking
> about comment 2.
According to comment 4, it's e10s enabled and is different from bug 1356695.

According to the value ui.osk.debug.keyboardDisplayReason is "IKPOS: Touch screen not found.", looks like OS reports that the device isn't an integrated touch.