** Description changed:

  [ Impact ]
  
  Upstream issue: https://gitlab.gnome.org/GNOME/gtk/-/issues/7515
  
  - Touchscreens are under "Virtual core pointer" virtual device in X11, and 
the virtual device is recognized as a `GDK_SOURCE_MOUSE`.
  - in `gdk/x11/gdk/x11/gdkdevicemanager-xi2.c`, `gdk_touch_event_new` is 
passed with the virtual device.
  - There are many places that checks whether the event is from touchscreen or 
mouse, by using `gdk_device_get_source` on the device included in the event 
above, which is `GDK_SOURCE_MOUSE` despite a touchscreen physical device is 
used.
  
  This issue caused bugs for LP: #2051886 and LP: #2119065, as they
  interpret touchscreen input as mouse events, and expect it to input like
  a mouse.
  
  [ Test Plan ]
  
  0. Obtain a machine with a touchscreen
  1. Log in to Ubuntu (on Xorg)
  2. Run `GDK_DEBUG=input nautilus`
  3. Verify in the terminal output that there exists an input device matching:
  """
  input device:
-         name: Virtual core pointer
-         type: logical
-         source: direct touch
+         name: Virtual core pointer
+         type: logical
+         source: direct touch
  """
  
  4. Open the debug console with Ctrl+Alt+D
  5. Navigate to Recorder
  6. Click the "Record frames" button
  7. Focus nautilus
  8. Click anywhere
  9. Switch back to the recorder window
  10. Select the "Touch Begin" event
  11. Verify that it originates from a device named "Virtual core pointer touch"
  
  [ Regression Test Plan ]
  
  Install and test gtk4-demo (from the gtk-4-examples package) as well as
  a few other GTK/GNOME applications like nautilus and gnome-text-editor,
  and verify that they continue to launch and work as expected without
  
  [ Where problems could occur ]
  
  The patch only affects X11 and couldn't possibly regress Wayland.
  The patch affects general input handling in GTK4, so a regression test plan 
is included to ensure that GTK applications still behave as expected.
+ 
+ [ Other Info ]
+ 
+ The bug status in resolute and questing is Invalid because there is no
+ Ubuntu/GNOME on Xorg anymore.
  
  ---
  ProblemType: Bug
  ApportVersion: 2.28.1-0ubuntu3.8
  Architecture: amd64
  CasperMD5CheckMismatches: ./.disk/casper-uuid-oem ./casper/initrd 
./casper/minimal.standard.live.hotfix.size ./casper/minimal.standard.live.size 
./casper/minimal.manifest ./casper/minimal.standard.manifest 
./casper/minimal.standard.size ./casper/minimal.hotfix.size 
./casper/minimal.standard.live.hotfix.squashfs 
./casper/minimal.standard.hotfix.squashfs ./casper/minimal.standard.hotfix.size 
./casper/minimal.hotfix.squashfs ./casper/minimal.standard.live.manifest 
./casper/minimal.size ./boot/grub/grub.cfg
  CasperMD5CheckResult: fail
  CurrentDesktop: ubuntu:GNOME
  DistributionChannelDescriptor:
   # This is the distribution channel descriptor for Ubuntu 24.04 for Dell
   # For more information see 
http://wiki.ubuntu.com/DistributionChannelDescriptor
   canonical-oem-somerville-noble-oem-24.04b-20250714-538
  DistroRelease: Ubuntu 24.04
  InstallationDate: Installed on 2025-07-15 (15 days ago)
  InstallationMedia: Ubuntu OEM 24.04.2 LTS "Noble Numbat" - Release amd64 
(20250714)
  Package: libgtk-4-1 4.14.5+ds-0ubuntu0.1
  PackageArchitecture: amd64
  ProcVersionSignature: Ubuntu 6.11.0-1025.25-oem 6.11.11
  Tags: noble
  Uname: Linux 6.11.0-1025-oem x86_64
  UpgradeStatus: No upgrade log present (probably fresh install)
  UserGroups: adm cdrom dip lpadmin plugdev sudo users
  _MarkForUpload: True

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https://bugs.launchpad.net/bugs/2119066

Title:
  X11 touchscreen events are handled as mouse events

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