gnome-shell crashed with SIGSEGV in cogl_matrix_stack_pop() from cogl_framebuffer_pop_matrix() from clutter_actor_paint() from clutter_actor_real_paint() from clutter_actor_continue_paint()

This bug was fixed in the package gnome-shell - 3.36.1-4ubuntu1

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gnome-shell (3.36.1-4ubuntu1) focal; urgency=medium

  * Merge with debian, with new upstream releases and cherry-picked fixes:
    - Lockscreen password field is stretched on enter (LP: #1869916)
    - Downscaled lockscreen background with fractional scaling (LP: #1866851)
    - Volume keys doesn't always produce a sound (LP: #1870958)
    - Shell crashes when using show-apps button in dock (LP: #1868659)
    - App folders improvements
    - Don't load app infos in the main thread
  * debian/patches:
    - Refreshed
  * d/p/ubuntu/desktop_detect.patch:
    - No need to include desktop.js into the prefs gresources anymore
  * Remaining changes with debian:
    - Replace gnome-backgrounds dep with ubuntu-wallpapers and Suggests
      gnome-themes-standard-data, gnome-backgrounds
    - Add some Recommends:
      + ubuntu-session (| gnome-session) to have the ubuntu session available
      + xserver-xorg-legacy
      + yaru-theme-gnome-shell for the default ubuntu theming
    - Update debian/gbp.conf with Ubuntu settings
    - gnome-shell-common.prerm: Remove deprecated ubuntu theme alternative
    - ubuntu/desktop_detect.patch:
      + add caching for desktop detection to avoid querying the current
        desktop env variable as iterate through the list each time. For the
        time of the Shell process, we can expect this env variable to stay
        stable.
    - ubuntu/smarter_alt_tab.patch:
      + quick alt-tab (without showing up the switcher) switch only between
        the last window of the last 2 applications to be focused instead of
        raising all windows of those apps.
    - ubuntu/lightdm-user-switching.patch:
      + Allow user switching when using LightDM.
    - ubuntu/lock_on_suspend.patch
      + Respect Ubuntu's lock-on-suspend setting.
    - ubuntu/background_login.patch
      + Change default background color as we modified the default GDM color
        for our ubuntu session.
    - ubuntu/gdm_alternatives.patch
      + Add support for GDM3 theme alternatives
    - optional-hot-corner.patch
      + enable patch proposed by upstream developer already in package (but
        not in series) to add a settings for optional hot corner activation.
    - main-show-an-error-message-on-gnome-shell-crash.patch,
      global-make-possible-to-set-debug-flags-dynamically.patch,
      main-increase-the-granularity-of-backtraces-in-SHELL_DEBU.patch,
      main-add-backtrace-crashes-all-and-backtrace-all.patch,
      sessionMode-add-support-for-debugFlags-parameter.patch:
      + Improve debug JS tracing for crash reports
    - st-scroll-view-Handle-the-case-where-scrollbars-are-NULL.patch:
      + Fix crash on theme changes
    - ubuntu/search-call-XUbuntuCancel-method-on-providers-when-no-dat.patch:
      + stop searches when requested from UI
    - magnifier-Show-cursor-when-magnifier-is-enabled-and-scale.patch:
      + Show monitor scaled cursor when magnifier is enabled
    - Break gnome-shell-extension-desktop-icons (<< 19.01.3+git20190814)

  [ Daniel van Vugt ]
  * d/p/ubuntu/keep-ubuntu-logo-bright-lp1867133-v1.patch:
     Stop the Ubuntu logo f...