Bug#800035: Screenshot key bindings work on lock screen

[Josh Triplett]

Package: gnome-shell
Version: 3.16.3-2
Severity: normal

While on the lock screen, pressing Ctrl-PrintScreen will flash the
screen as though taking a screenshot of the lock window, and
Ctrl-Shift-PrintScreen will switch to the plus-shaped cursor and allow
selecting a region to screenshot.  As far as I can tell, the screenshot
doesn't actually get saved anywhere; however, the keybindings shouldn't
work at all.  (It looks like PrintScreen doesn't work, but the rest do.)

-- System Information:
Debian Release: stretch/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 4.1.0-2-amd64 (SMP w/4 CPU cores)
Locale: LANG=C.UTF-8, LC_CTYPE=C.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages gnome-shell depends on:
ii  dconf-gsettings-backend [gsettings-backend]  0.24.0-2
ii  evolution-data-server                        3.16.5-1
ii  gir1.2-accountsservice-1.0                   0.6.40-3
ii  gir1.2-atspi-2.0                             2.16.0-1
ii  gir1.2-caribou-1.0                           0.4.18.1-1
ii  gir1.2-clutter-1.0                           1.24.0-1
ii  gir1.2-freedesktop                           1.44.0-1+b2
ii  gir1.2-gcr-3                                 3.16.0-1
ii  gir1.2-gdesktopenums-3.0                     3.18.0-1
ii  gir1.2-gdm3                                  3.14.2-2
ii  gir1.2-gkbd-3.0                              3.6.0-1
ii  gir1.2-glib-2.0                              1.44.0-1+b2
ii  gir1.2-gnomebluetooth-1.0                    3.16.1-1
ii  gir1.2-gnomedesktop-3.0                      3.16.2-2
ii  gir1.2-gtk-3.0                               3.16.6-1
ii  gir1.2-gweather-3.0                          3.16.1-1
ii  gir1.2-ibus-1.0                              1.5.10-1
ii  gir1.2-mutter-3.0                            3.16.3-1
ii  gir1.2-networkmanager-1.0                    1.0.6-1
ii  gir1.2-nmgtk-1.0                             1.0.6-2
ii  gir1.2-pango-1.0                             1.36.8-3
ii  gir1.2-polkit-1.0                            0.105-12
ii  gir1.2-soup-2.4                              2.50.0-2
ii  gir1.2-telepathyglib-0.12                    0.24.1-1
ii  gir1.2-telepathylogger-0.2                   0.8.1-1
ii  gir1.2-upowerglib-1.0                        0.99.3-1+b2
ii  gjs                                          1.43.3-2
ii  gnome-backgrounds                            3.16.0-1
ii  gnome-icon-theme-symbolic                    3.12.0-1
ii  gnome-settings-daemon                        3.16.3-1
ii  gnome-shell-common                           3.16.3-2
ii  gnome-themes-standard                        3.16.2-2
ii  gsettings-desktop-schemas                    3.18.0-1
ii  libatk-bridge2.0-0                           2.16.0-2
ii  libatk1.0-0                                  2.18.0-1
ii  libc6                                        2.19-22
ii  libcairo2                                    1.14.2-2
ii  libcanberra-gtk3-0                           0.30-2.1
ii  libcanberra0                                 0.30-2.1
ii  libclutter-1.0-0                             1.24.0-1
ii  libcogl-pango20                              1.22.0-1
ii  libcogl20                                    1.22.0-1
ii  libcroco3                                    0.6.8-3+b1
ii  libdbus-glib-1-2                             0.102-1
ii  libecal-1.2-18                               3.16.5-1
ii  libedataserver-1.2-20                        3.16.5-1
ii  libgcr-base-3-1                              3.16.0-1
ii  libgdk-pixbuf2.0-0                           2.32.0-1
ii  libgirepository-1.0-1                        1.44.0-1+b2
ii  libgjs0e [libgjs0-libmozjs-24-0]             1.43.3-2
ii  libglib2.0-0                                 2.46.0-1
ii  libgstreamer1.0-0                            1.5.90-1
ii  libgtk-3-0                                   3.16.6-1
ii  libical1a                                    1.0.1-0.1
ii  libjson-glib-1.0-0                           1.0.4-1
ii  libmozjs-24-0                                24.2.0-3
ii  libmutter0f                                  3.16.3-1
ii  libnm-glib4                                  1.0.6-1
ii  libnm-util2                                  1.0.6-1
ii  libpango-1.0-0                               1.36.8-3
ii  libpangocairo-1.0-0                          1.36.8-3
ii  libpolkit-agent-1-0                          0.105-12
ii  libpolkit-gobject-1-0                        0.105-12
ii  libpulse-mainloop-glib0                      7.0-1
ii  libpulse0                                    7.0-1
ii  libsecret-1-0                                0.18.3-1
ii  libstartup-notification0                     0.12-4
ii  libsystemd0                                  226-3
ii  libtelepathy-glib0                           0.24.1-1
ii  libx11-6                                     2:1.6.3-1
ii  libxfixes3                                   1:5.0.1-2+b2
ii  mutter                                       3.16.3-1
ii  python3                                      3.4.3-4
ii  telepathy-mission-control-5                  1:5.16.3-1

Versions of packages gnome-shell recommends:
ii  gdm3                  3.14.2-2
ii  gkbd-capplet          3.6.0-1
ii  gnome-contacts        3.18.0-1
ii  gnome-control-center  1:3.16.3-1
ii  gnome-user-guide      3.16.1-1
ii  unzip                 6.0-18

gnome-shell suggests no packages.

-- no debconf information