Restore previous configuration after turning off fractional scaling does not work

[Marco Trevisan (Treviño)]

[ Impact ]

It's not possible to restore the application a non-fractional scaling configuration when fractional scaling was previously enabled and applied.

[ Test case ]

1. From control center, display panel, enable fractional scaling
2. Set scaling to some fractional value and apply and confirm it.
3. Turn off the fractional scaling switch and apply it
4. Fractional scaling should be reverted to the selected integer scaling.
5. When gnome-shell shows the confirmation dialog, click "Revert Settings"
6. Expect the fractional scaling to be re-enabled and applied as it used to be

[ Regression potential ]
- Configuration can't be applied
- Scaling (fractional or not) is not properly applied in single and multi-monitor
- Fractional scaling can't be toggled anymore

[Launchpad Janitor (janitor)]

This bug was fixed in the package mutter - 3.36.3-1ubuntu2

---------------
mutter (3.36.3-1ubuntu2) groovy; urgency=medium

  * debian/control:
    - Revert BD on adwaita-icon-theme 3.36.1-2ubuntu3. It was just temporary fix.
  * d/p/x11-Add-support-for-fractional-scaling-using-Randr.patch:
    - Use pre-computed CRTC layout size for computing screen size (LP: #1874567,
      LP: #1873403)
    - Decouple the output mode from layout mode capabilities (LP: #1876894,
      LP: #1886996)
    - Ensure we notify CRTC changes on integer scaling changes (LP: #1876894)
    - Apply proper layout monitor config when using fractional scaling
      (LP: #1884754)
    - Restore the fractional settings when reverting to fractional layout
      (LP: #1886996)
  * debian/libmutter-6-0.symbols: Add new private symbol

 -- Marco Trevisan (Treviño) <email address hidden> Sat, 11 Jul 2020 00:44:33 +0200

[Brian Murray (brian-murray)]

Hello Marco, or anyone else affected,

Accepted mutter into focal-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/mutter/3.36.4-0ubuntu0.20.04.1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-focal to verification-done-focal. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-focal. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Łukasz Zemczak (sil2100)]

Hello Marco, or anyone else affected,

Accepted mutter into focal-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/mutter/3.36.4-0ubuntu0.20.04.2 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-focal to verification-done-focal. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-focal. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Marco Trevisan (Treviño) (3v1n0)]

Confirm the test case works correctly here:

❯ apt-cache policy libmutter-6-0
libmutter-6-0:
  Installed: 3.36.4-0ubuntu0.20.04.2
  Candidate: 3.36.4-0ubuntu0.20.04.2
  Version table:
 *** 3.36.4-0ubuntu0.20.04.2 500
        500 http://it.archive.ubuntu.com/ubuntu focal-proposed/main amd64 Packages
        100 /var/lib/dpkg/status
     3.36.3-0ubuntu0.20.04.1 500
        500 http://it.archive.ubuntu.com/ubuntu focal-updates/main amd64 Packages
     3.36.1-3ubuntu3 500
        500 http://it.archive.ubuntu.com/ubuntu focal/main amd64 Packages

❯ apt-cache policy gnome-control-center
gnome-control-center:
  Installed: 1:3.36.4-0ubuntu1
  Candidate: 1:3.36.4-0ubuntu1
  Version table:
 *** 1:3.36.4-0ubuntu1 500
        500 http://it.archive.ubuntu.com/ubuntu focal-updates/main amd64 Packages
        100 /var/lib/dpkg/status
     1:3.36.1-1ubuntu5 500
        500 http://it.archive.ubuntu.com/ubuntu focal/main amd64 Packages

[Launchpad Janitor (janitor)]

This bug was fixed in the package mutter - 3.36.4-0ubuntu0.20.04.2

---------------
mutter (3.36.4-0ubuntu0.20.04.2) focal; urgency=medium

  * xrandr-scaling: Never try to set invalid screen sizes (LP: #1889090)

mutter (3.36.4-0ubuntu0.20.04.1) focal; urgency=medium

  * New upstream stable release (LP: #1887998)
    - Fix crash on area screenshots with fractional scaling
    - Do not paint textures of fully obscured windows
    - Turn off CRTCs as well when enabling DPMS
    - Improve selection support
    - Use a more appropriate combine function on opaque areas
    - Fix remote desktop being broken without screencast session
    - Fix popovers disappearing on wayland and HiDPI
    - Fixed crashes (LP: #1870867, LP: #1857947)
    - Plugged memory leaks
  * d/p/screen-cast-Let-the-reason-for-recording-determine-what-t.patch,
    d/p/screen-cast-src-Add-flag-to-maybe_record.patch,
    d/p/screen-cast-src-Fix-signedness-of-timestamp-field.patch,
    d/p/screen-cast-src-Make-record-functions-return-an-error-whe.patch,
    d/p/screen-cast-src-Make-the-two-record-vfuncs-more-similarly.patch,
    d/p/screen-cast-src-Record-follow-up-frame-after-timeout.patch,
    d/p/screen-cast-src-Remove-follow-up-timeout-source-on-disabl.patch,
    d/p/screen-cast-src-Use-G_USEC_PER_SEC-instead-of-1000000.patch,
    d/p/screen-cast-window-stream-src-Fix-indentation.patch:
    - Import more fixes for screencasting and remote desktop
  * d/p/x11-Add-support-for-fractional-scaling-using-Randr.patch:
    - Don't export patch-only private symbol
  * debian/libmutter-6-0.symbols:
    - Remove ubuntu-only private symbol

mutter (3.36.3-0ubuntu0.20.04.2) focal; urgency=medium

  * debian/control:
    - Revert BD on adwaita-icon-theme 3.36.1-2ubuntu3. It was just temporary fix
  * d/p/x11-Add-support-for-fractional-scaling-using-Randr.patch:
    - Use pre-computed CRTC layout size for computing screen size (LP: #1874567,
      LP: #1873403)
    - Decouple the output mode from layout mode capabilities (LP: #1876894,
      LP: #1886996)
    - Ensure we notify CRTC changes on integer scaling changes (LP: #1876894)
    - Apply proper layout monitor config when using fractional scaling
      (LP: #1884754)
    - Restore the fractional settings when reverting to fractional layout
      (LP: #1886996)
  * debian/libmutter-6-0.symbols: Add new private symbol

 -- Marco Trevisan (Treviño) <email address hidden> Mon, 27 Jul 2020 17:04:41 +0200

[Łukasz Zemczak (sil2100)]

The verification of the Stable Release Update for mutter has completed successfully and the package is now being released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.