OSK Enter, space and backspace keys don't work when typing in Greek

Please try live booting Ubuntu 19.04 and tell us if it has the same bug:

  http://cdimages.ubuntu.com/daily-live/current/

If the bug is still present in 19.04 then please report it to the GNOME developers here:

  https://gitlab.gnome.org/GNOME/gnome-shell/issues

I opened Ubuntu 19.04 in a VM and selected The Try Ubuntu option. The bug is still present. This is the bug in gitlab gnome: https://gitlab.gnome.org/GNOME/gnome-shell/issues/1079

Thank you for reporting this bug to Ubuntu.
Ubuntu 19.04 (disco) reached end-of-life on January 23, 2020.

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The problem exists in Ubuntu 20.04 desktop. I use the default onscreen keyboard. I have added a second language (greek) and it works fine on a real keyboard, but on the onscreen keyboard, some keys don't work (don't do anything) i.e. the backspace and the enter.
Do you know where can I find the onscreen key mapping and correct it?

Upstream says it is fixed in https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1955

This bug was fixed in the package mutter - 41.3-1ubuntu1

---------------
mutter (41.3-1ubuntu1) jammy; urgency=medium

  * Merge with debian, includes these upstream changes:
    - window: Don't change workspaces of unmanaged windows (LP: #1933996)
    - backend: Reset idletime when unplugging the power cable (LP: #1945121)
    - clutter/text: Invalidate actor paint volume when it has changed
      (LP: #1882291)
    - backends/native: Ensure pointer is onscreen in input thread (LP: #1933186)
    - OSK Enter, space and backspace keys don't work when typing in Greek
      (LP: #1820523)
    - window: Don't change workspaces of unmanaged windows (LP: #1932328)
  * Remainig changes with debian:
    - debian/gbp.conf: update upstream branch to point to ubuntu/master
    - debian/patches/x11-Add-support-for-fractional-scaling-using-Randr.patch:
      + X11: Add support for fractional scaling using Randr

mutter (41.3-1) unstable; urgency=medium

  * New upstream release:
    - Check keyboard serials for activation
    - Fix mixed up refresh rates in multi-monitor setups (LP: #1788535)
    - Allow disabling HW cursors
    - Improve damage handling (LP: #1872870)
    - Consider xrandr flags for advertised modes
    - Ensure constraints after client resize
    - window-group: Disable culling when rendinging clone to offscreen buffer
    - Fix workspace switch animation in default plugin
    - Fix unfullscreening of window that were mapped fullscreen
    - Fix DMA-BUF screencasts with unredirected fullscreen windows
    - Fix orientation changes on devices with 90°

mutter (41.2-2) unstable; urgency=medium

  * Team upload
  * d/p/Consistently-pass-timestamp-as-uint64-when-creating-MetaS.patch:
    Add proposed patch to fix FTBFS on 32-bit architectures
  * d/patches: Update to 41.2-6-g7b64c159a
    - Surface damage viewport improvements
  * Update patch metadata with upstream status

mutter (41.2-1) unstable; urgency=medium

  * Team upload

  [ Simon McVittie ]
  * New upstream release
  * d/patches: Drop patches that were applied upstream
  * d/patches: Update to upstream gnome-41 branch commit 41.2-3-g5d0c26631
    - wayland: Check keyboard serials for activation
    - Sync refresh rate to the correct monitor for maximized/full-screen
      apps in a multi-monitor layout
    - Add a debug environment variable to disable hardware cursors for
      faulty hardware and drivers

  [ Laurent Bigonville ]
  * debian/rules: Disable systemd support on non-linux architectures

mutter (41.1-1) unstable; urgency=medium

  * Team upload
  * New upstream release
  * Drop a patch that came from upstream
  * Update Lintian overrides
  * Replace patches for #995929 with the version that was applied upstream
  * Remove workaround for #994806
  * d/libmutter-9-0.symbols: Ignore removal of clutter_stage_capture_into.
    Nothing else in Debian references this symbol, except for forks of
    the mutter codebase.

mutter (41.0-5) unstable; urgency=medium

  * Team upload
  * Merge packaging from unstable
    - No changes relative to 41.0-4, except for the changelog
  * Close #995929 via changelog.
    The patches in 41.0-4 seem to have been successful.
  * Release to...