gnome-shell activities / application icon touches not fully registering

[Joe Barnett]

On a dell xps 15 2-in-1 (model 9575), the touchscreen mostly works. However, in gnome-shell, touching the top-left 'Activities' menu results in a quick flash of the menu button, but not the launching of the overview. Once in the overview (via mouse/keyboard/swipe-from-left), touching on an application icon (in either the left tray or the applications grid) results in the application icon flashing, but not activating. A long-touch will bring up a menu in which touching on "new window" works properly. Additionally, touching the "show applications" grid button works, as do other components of the top bar, its only the the "activities" menu button and app icon launchers that are "registering" a touch but not activating properly.

ProblemType: Bug
DistroRelease: Ubuntu 18.10
Package: gnome-shell 3.30.0-3ubuntu1
ProcVersionSignature: Ubuntu 4.18.0-8.9-generic 4.18.7
Uname: Linux 4.18.0-8-generic x86_64
ApportVersion: 2.20.10-0ubuntu11
Architecture: amd64
CurrentDesktop: GNOME
Date: Wed Oct 10 09:13:40 2018
DisplayManager: gdm3
InstallationDate: Installed on 2018-09-26 (14 days ago)
InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725)
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: gnome-shell
UpgradeStatus: Upgraded to cosmic on 2018-09-28 (11 days ago)

[Daniel van Vugt (vanvugt)]

Please start by disabling your extensions:

b'org.gnome.shell' b'enabled-extensions' b"['<email address hidden>', '<email address hidden>', '<email address hidden>', '<email address hidden>', 'audio-output-switcher@anduchs', 'audio-input-switcher@anduchs']"

and verify the bug still occurs without them.

[Joe Barnett (thejoe)]

Disabling extensions in the same session still shows the same behavior. Logging out and back in again with them still disabled shows the same behavior on the "Activities" button, but app launchers respond to touch events appropriately. Re-enabling them in the same session keeps the same state ("Activities" button bad, app launchers good)

[Daniel van Vugt (vanvugt)]

There might be some relation to bug 1725384.

[Joe Barnett (thejoe)]

maybe, although I'm using the vanilla gnome session, so the ubuntu-dock extension shouldn't be involved.

[Mario Vukelic (kreuzsakra)]

FWIW and FYI, I cannot repro this on Cosmic with Dell XPS 15 9575

[Joe Barnett (thejoe)]

Doing a little more testing, it looks like everything works fine under Xorg, but am still seeing the activities button behavior under Wayland.

[Joe Barnett (thejoe)]

And with more testing, it seems like the activities button target is smaller and/or lower under Wayland than it is in Xorg. I can get it to work if i aim for the bottom of the black top bar, vs the middle of it (while aiming for the middle results in the flash, but not activation of the Activites text).

[Mario Vukelic (kreuzsakra)]

@Joe, at least in Wayland (did not test in X yet) the touch does not register when I touch anywhere right at the edge of the display. That goes for the whole perimeter of the display. E.g., srollbars of maximized windows on the right, dock launchers on the left, and the Gnome panel menu top right are not triggered in this case.

The same goes for the Activities menu, but when I aim e.g. for the middle of Activities or the middle of the panel menu, they are triggered fine. And I can never repro this "flash", either the touch is ignored or the Activities open properly.

[Daniel van Vugt (vanvugt)]

Thank you for reporting this bug to Ubuntu.
Ubuntu 18.10 (cosmic) reached end-of-life on July 18, 2019.

See this document for currently supported Ubuntu releases:
https://wiki.ubuntu.com/Releases

We appreciate that this bug may be old and you might not be interested in discussing it any more. But if you are then please upgrade to the latest Ubuntu version and re-test. If you then find the bug is still present in the newer Ubuntu version, please add a comment here telling us which new version it is in and change the bug status to Confirmed.