1396427 - Trying to select text with touch screen on Linux causes touch event to get "stuck"

Status: UNCONFIRMED

(Core :: DOM: UI Events & Focus Handling, defect, P3)

Description

[konrad]

User Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.78 Safari/537.36 OPR/47.0.2631.55
Firefox for Android

Steps to reproduce:

This was done on Arch Linux x86_64 with touch screen configured and KDE desktop environment. This was reproduced on both stable and nightly (57.0a1).

1. Start Firefox with `env MOZ_USE_XINPUT=1`
2. Hold finger over text for a second to select text
3. Try touching any UI interface (for instance New Tab button)


Actual results:

Text is selected AND right click menu appears. UI is unusable anymore with touch anymore, and seems to scroll slower by moving the finger to scroll. It's not possible to remove selection by touching outside of it.

Additionally a following message appears in console. The address will change between runs.

(firefox:27812): GLib-GObject-WARNING **: gsignal.c:3492: signal name 'selection_changed' is invalid for instance '0x7f1515451c40' of type 'MaiAtkType139'


Expected results:

The text should be selected, and touch shouldn't behave as if I kept touching the screen even after stopping to do so.

Touch screen interface seems to work as expected in Opera browser.

Comment 1

[konrad]

I selected that this is tablet in bug tracker, because it technically is. However, it is not Firefox for Android, but rather obscure operating system with touch screen support known as Linux (which may make this bug hard to reproduce).

Comment 2

[konrad]

Attachment: Video of a bug, mouse cursor represents location of a finger

Recorded a video of a bug. Mouse pointer represents touch input in it. Note that mouse cursor appears even when the display wasn't touched, so it may be a bit confusing (but it's possible to tell when touch stopped moving by cursor not moving, with exception for holding a finger for a few seconds over "emphasizes" word).

Comment 3

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

What's the preference value dom.w3c_touch_events.enabled ? I think MOZ_USE_XINPUT2 is the one we support, isn't it?

Comment 4

[Ming-Chou Shih [:stone]]

dom.w3c_touch_events.enabled is the preference to support W3C touch events. MOZ_USE_XINPUT2=1 is a configuration to use xinput2 as the input source on Linux.

Comment 5

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

(In reply to Ming-Chou Shih [:stone] from comment #4)
> dom.w3c_touch_events.enabled is the preference to support W3C touch events.
> MOZ_USE_XINPUT2=1 is a configuration to use xinput2 as the input source on
> Linux.

Sorry let me express myself clearer - is it expected ' env MOZ_USE_XINPUT=1" work and effective on Firefox ? I am asking because I didn't get this end variable in searchfox, but I did see MOZ_USE_XINPUT2. If it's not because of the env setting, any ideas of where the problem is. Thank you.

Comment 6

[Ming-Chou Shih [:stone]]

(In reply to Hsin-Yi Tsai [:hsinyi] from comment #5)
> (In reply to Ming-Chou Shih [:stone] from comment #4)
> > dom.w3c_touch_events.enabled is the preference to support W3C touch events.
> > MOZ_USE_XINPUT2=1 is a configuration to use xinput2 as the input source on
> > Linux.
> 
> Sorry let me express myself clearer - is it expected ' env MOZ_USE_XINPUT=1"
> work and effective on Firefox ? I am asking because I didn't get this end
> variable in searchfox, but I did see MOZ_USE_XINPUT2.

Is it a typo?

Comment 7

[konrad]

dom.w3c_touch_events.enabled was set to 2, the issue still exists with 1 however.

Comment 8

[konrad]

Also my mistake, the command I use was `env MOZ_USE_XINPUT2=1 firefox-nightly`

Comment 9

[konrad]

Also having dom.w3c_touch_events.enabled set to 0 causes text to be unable to be selected with touch, but the issue still happens when context menu appears.

Comment 10

[Ming-Chou Shih [:stone]]

This bug looks like the same as bug 1321069.

Comment 11

[Particula]

I can confirm this bug with FF 57.
Until restart or detach tab to new window I am unable to use touch input correctly.