second, dead, mouse pointer left on screen after login, x11 session

Bug #1829221 reported by Rachel Greenham
74
This bug affects 16 people
Affects Status Importance Assigned to Milestone
mutter (Ubuntu)
Confirmed
Undecided
Unassigned

Bug Description

This seems to have become repeatable, and applies even on the first login session immediately after booting the computer. I don't know if this is the right package to report against; another possible culprit: gdm:

When I log into the default "Ubuntu" session (ie: on xorg), gdm's mouse pointer remains on screen during the screen blank, and after the gnome desktop comes up. It stays on the top just like you'd expect of the mouse pointer, but it's immobile and unresponsive. It's left at the same position on the screen that it was while using gdm, and is the same size as it was in gdm (ie: gdm is not scaled, but gnome session desktop scaled to 150% - the *working* in-session mouse pointer is also 150% larger than gdm's dead one).

It looks like gdm and gnome are running in the same x11 session? Seeing as the mouse pointer stays solid *during* the transition from gdm into the gnome desktop. Not even a flicker. It's almost as if we're trying to have smooth transitions for these sorts of things, which is good of course, but maybe is a bug in that?

It disappears when I log into a Wayland session, it appears only to affect x11 sessions.

I've taken to just moving the mouse pointer to the far bottom right corner of the screen before logging in, so at least it's not very intrusive.

There are a few reports of similar in askubuntu from a few years back, but with no helpful or applicable solution. eg:

https://askubuntu.com/questions/521241/i-have-two-cursors-on-my-screen-one-of-which-is-always-on-top-and-will-never-mo
https://askubuntu.com/questions/598096/14-04-second-mouse-pointer-stuck-in-middle-of-the-screen

To answer the points made there, the xinput --list output is shown below. Executing that command and rebooting makes no difference. In the Displays Prefs there is no second "Unknown" display to disable. (The machine has precisely one display, and that's all Settings sees. It's a desktop, not a laptop, and it only has an AMD Vega integrated graphics. It also has only one mouse.)

rachel@twilight:~$ xinput --list
⎡ Virtual core pointer id=2 [master pointer (3)]
⎜ ↳ Virtual core XTEST pointer id=4 [slave pointer (2)]
⎜ ↳ HID 04b4:3003 Mouse id=9 [slave pointer (2)]
⎜ ↳ HID 04b4:3003 Consumer Control id=11 [slave pointer (2)]
⎜ ↳ Microsoft Microsoft® Nano Transceiver v1.0 Mouse id=15 [slave pointer (2)]
⎜ ↳ Microsoft Microsoft® Nano Transceiver v1.0 Consumer Control id=16 [slave pointer (2)]
⎜ ↳ Microsoft Microsoft® Nano Transceiver v1.0 Consumer Control id=17 [slave pointer (2)]
⎣ Virtual core keyboard id=3 [master keyboard (2)]
    ↳ Virtual core XTEST keyboard id=5 [slave keyboard (3)]
    ↳ Power Button id=6 [slave keyboard (3)]
    ↳ Power Button id=7 [slave keyboard (3)]
    ↳ HID 04b4:3003 id=8 [slave keyboard (3)]
    ↳ HID 04b4:3003 System Control id=10 [slave keyboard (3)]
    ↳ HID 04b4:3003 Keyboard id=12 [slave keyboard (3)]
    ↳ Dell Dell AC511 USB SoundBar id=13 [slave keyboard (3)]
    ↳ Microsoft Microsoft® Nano Transceiver v1.0 id=14 [slave keyboard (3)]
    ↳ Microsoft Microsoft® Nano Transceiver v1.0 System Control id=18 [slave keyboard (3)]
    ↳ Eee PC WMI hotkeys id=19 [slave keyboard (3)]
    ↳ HID 04b4:3003 Consumer Control id=20 [slave keyboard (3)]
    ↳ Microsoft Microsoft® Nano Transceiver v1.0 Consumer Control id=21 [slave keyboard (3)]
    ↳ Microsoft Microsoft® Nano Transceiver v1.0 Consumer Control id=22 [slave keyboard (3)]

(I don't know what's with the duplicated MS Nano Transceiver Consumer Control entries)

I thought of a couple of things to try after starting to write this ticket but didn't want to lose the ticket in progress, so will add comments if they show up anything. In particular, I am running the experimental feature to enable xrandr fractional scaling. This issue didn't show up right after enabling that, only a couple of days later, so it didn't seem immediately relevant.

Also, trying with a different pointing device attached in case that transceiver is doing something odd. (never had problems before, had it years, no idea if that doubling-up has always been there.)

ProblemType: Bug
DistroRelease: Ubuntu 19.04
Package: ubuntu-session 3.32.0-1ubuntu1
ProcVersionSignature: Ubuntu 5.0.0-15.16-generic 5.0.6
Uname: Linux 5.0.0-15-generic x86_64
ApportVersion: 2.20.10-0ubuntu27
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Wed May 15 11:38:19 2019
InstallationDate: Installed on 2019-05-11 (3 days ago)
InstallationMedia: Ubuntu 19.04 "Disco Dingo" - Release amd64 (20190416)
PackageArchitecture: all
SourcePackage: gnome-session
UpgradeStatus: No upgrade log present (probably fresh install)

Revision history for this message
Rachel Greenham (rachel-strangenoises) wrote :
Revision history for this message
Rachel Greenham (rachel-strangenoises) wrote :

It does appear to be related to the xrandr scaling experimental feature, after all. Revert that to default and the issue disappears. Guessing that probably makes it a mutter bug, and being of an experimental feature at that is hopefully of interest to someone but not urgent. In view of that didn't test switching pointing device.

no longer affects: gnome-session (Ubuntu)
Revision history for this message
Daniel van Vugt (vanvugt) wrote :

Thank you for taking the time to report this bug and helping to make Ubuntu better. This particular bug has already been reported and is a duplicate of bug 1827428, so it is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Feel free to continue to report any other bugs you may find.

tags: added: xrandr-scaling
tags: added: cursor
Revision history for this message
Launchpad Janitor (janitor) wrote :

Status changed to 'Confirmed' because the bug affects multiple users.

Changed in mutter (Ubuntu):
status: New → Confirmed
Revision history for this message
Travis Fields (cyberious) wrote :

I was able to get rid of this by changing the display scaling back to 100% and than I resumed the display scale that I had wanted.

Revision history for this message
Johannes Scheller (johannes-scheller) wrote :

Travis solution worked however after the next reboot the problem reappears. Any idea how to fix it permanently?

Revision history for this message
Lorenzo Dellacà (mindoverflow) wrote :

I don't think there is an official solution to this yet, however, in my Ubuntu 20.04 (and then also 20.10) installation I was able to automatically fix it every login by using this very small program I developed: https://github.com/mind-overflow/gnome-fs-duplicate-cursor-fix

To post a comment you must log in.
This report contains Public information  
Everyone can see this information.

Other bug subscribers

Remote bug watches

Bug watches keep track of this bug in other bug trackers.