1538709 - Click events are still triggered when touch simulation is activated in RDM

Status: RESOLVED FIXED

(DevTools :: Responsive Design Mode, defect, P3)

Description

[Patrick Brosset <:pbro>]

Attachment: touch.html

Steps:

• open the attached HTML test case
• open RDM
• turn on touch simulation
• touch once in the canvas area (as in, click down then up, without moving)

The expectation is that the log area only displays touch events.
Result: instead, I see this:

click
mouseup
mousedown
touchend
touchstart:0.
touchstart:0...
touchstart.

Testing in Chrome's mobile view does what I expected. The log only shows this:

touchend
touchstart:0.
touchstart:0...
touchstart.

Comment 1

[Patrick Brosset <:pbro>]

Might be the same root cause as bug 1386796.

Comment 2

[Patrick Brosset <:pbro>]

This seems to be done on purpose: https://searchfox.org/mozilla-central/rev/56705678f5fc363be5e0237e1686f619b0d23009/devtools/server/actors/emulation/touch-simulator.js#284-327
And here is more information: https://developers.google.com/web/updates/2013/12/300ms-tap-delay-gone-away
I wonder, though, why does Chrome not do this.

Comment 3

[Brad Werth [:bradwerth]]

I'll take a look. We also seem to have an intermittent test in Bug 1442943 that's related to this issue.

Comment 4

[Martin Balfanz [:mbalfanz]]

Tested this with the latest Fenix and can confirm that it behaves similar to Chromes mobile view.

Comment 5

[Florens Verschelde :fvsch]

I can't reproduce on Nightly 77.0a1 (2020-04-10) on macOS with the attached test case.

• RDM with touch events simulation enabled: only logs touch events
• RDM with touch events simulation disabled: only logs click & mouse events

Might have been fixed in another bug?

Comment 6

[Micah [:mtigley] (she/her)]

Looks like this was fixed by Bug 1623941. I'll resolve this issue, but please feel free to re-open if you're experiencing this issue still.