Acho que isso é uma confusão entre as páginas upstream do XCFE.org que indicam que o Midori é um dos itens do xfce4 e o que está realmente instalado.
As dependências reais do pacote xfce4-goodies
que ele instala nem sequer fazem referência ao Midori em qualquer lugar. De apt-get install --dry-run xfce4-goodies
em uma caixa padrão do Ubuntu 16.04:
NOTE: This is only a simulation!
apt-get needs root privileges for real execution.
Keep also in mind that locking is deactivated,
so don't depend on the relevance to the real current situation!
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
libqmi-glib1 linux-headers-4.4.0-109 linux-headers-4.4.0-109-generic
linux-image-4.4.0-109-generic linux-image-extra-4.4.0-109-generic
Use 'apt autoremove' to remove them.
The following additional packages will be installed:
exo-utils hddtemp libexo-1-0 libexo-common libexo-helpers libgarcon-1-0
libgarcon-common libtagc0 libthunarx-2-0 libtumbler-1-0 libunique-1.0-0
libvte-common libvte9 libwnck-common libwnck22 libxfce4ui-1-0
libxfce4ui-common libxfce4util-bin libxfce4util-common libxfce4util7
libxfconf-0-2 lm-sensors mousepad ristretto thunar thunar-archive-plugin
thunar-data thunar-media-tags-plugin thunar-volman tumbler tumbler-common
xfburn xfce4-artwork xfce4-battery-plugin xfce4-clipman xfce4-clipman-plugin
xfce4-cpufreq-plugin xfce4-cpugraph-plugin xfce4-datetime-plugin xfce4-dict
xfce4-diskperf-plugin xfce4-fsguard-plugin xfce4-genmon-plugin
xfce4-mailwatch-plugin xfce4-mount-plugin xfce4-netload-plugin xfce4-notes
xfce4-notes-plugin xfce4-panel xfce4-places-plugin xfce4-power-manager
xfce4-power-manager-data xfce4-power-manager-plugins xfce4-screenshooter
xfce4-sensors-plugin xfce4-smartbookmark-plugin xfce4-systemload-plugin
xfce4-taskmanager xfce4-terminal xfce4-timer-plugin xfce4-verve-plugin
xfce4-wavelan-plugin xfce4-weather-plugin xfce4-whiskermenu-plugin
xfce4-xkb-plugin xfconf
Suggested packages:
ksensors devhelp fancontrol sensord read-edid i2c-tools
tumbler-plugins-extra xfce4-cellmodem-plugin xfce4-linelight-plugin
xfce4-messenger-plugin xfce4-mpc-plugin xfce4-radio-plugin xfswitch-plugin
xfce4-hdaps gigolo parole xsensors
The following NEW packages will be installed:
exo-utils hddtemp libexo-1-0 libexo-common libexo-helpers libgarcon-1-0
libgarcon-common libtagc0 libthunarx-2-0 libtumbler-1-0 libunique-1.0-0
libvte-common libvte9 libwnck-common libwnck22 libxfce4ui-1-0
libxfce4ui-common libxfce4util-bin libxfce4util-common libxfce4util7
libxfconf-0-2 lm-sensors mousepad ristretto thunar thunar-archive-plugin
thunar-data thunar-media-tags-plugin thunar-volman tumbler tumbler-common
xfburn xfce4-artwork xfce4-battery-plugin xfce4-clipman xfce4-clipman-plugin
xfce4-cpufreq-plugin xfce4-cpugraph-plugin xfce4-datetime-plugin xfce4-dict
xfce4-diskperf-plugin xfce4-fsguard-plugin xfce4-genmon-plugin xfce4-goodies
xfce4-mailwatch-plugin xfce4-mount-plugin xfce4-netload-plugin xfce4-notes
xfce4-notes-plugin xfce4-panel xfce4-places-plugin xfce4-power-manager
xfce4-power-manager-data xfce4-power-manager-plugins xfce4-screenshooter
xfce4-sensors-plugin xfce4-smartbookmark-plugin xfce4-systemload-plugin
xfce4-taskmanager xfce4-terminal xfce4-timer-plugin xfce4-verve-plugin
xfce4-wavelan-plugin xfce4-weather-plugin xfce4-whiskermenu-plugin
xfce4-xkb-plugin xfconf
0 upgraded, 67 newly installed, 0 to remove and 215 not upgraded.
Inst libxfce4util-common (4.12.1-2 Ubuntu:16.04/xenial [all])
Inst libxfce4util7 (4.12.1-2 Ubuntu:16.04/xenial [amd64])
Inst xfconf (4.12.0-2 Ubuntu:16.04/xenial [amd64])
Inst libxfconf-0-2 (4.12.0-2 Ubuntu:16.04/xenial [amd64])
Inst libxfce4ui-common (4.12.1-2 Ubuntu:16.04/xenial [all])
Inst libxfce4ui-1-0 (4.12.1-2 Ubuntu:16.04/xenial [amd64])
Inst libgarcon-common (0.4.0-2 Ubuntu:16.04/xenial [all])
Inst libgarcon-1-0 (0.4.0-2 Ubuntu:16.04/xenial [amd64])
Inst libexo-common (0.10.7-1 Ubuntu:16.04/xenial [all])
Inst libexo-helpers (0.10.7-1 Ubuntu:16.04/xenial [amd64])
Inst libexo-1-0 (0.10.7-1 Ubuntu:16.04/xenial [amd64])
Inst exo-utils (0.10.7-1 Ubuntu:16.04/xenial [amd64])
Inst libtagc0 (1.9.1-2.4ubuntu1 Ubuntu:16.04/xenial [amd64])
Inst thunar-data (1.6.11-0ubuntu0.16.04.2 Ubuntu:16.04/xenial-updates [all])
Inst libthunarx-2-0 (1.6.11-0ubuntu0.16.04.2 Ubuntu:16.04/xenial-updates [amd64])
Inst libtumbler-1-0 (0.1.31-2build2 Ubuntu:16.04/xenial [amd64])
Inst libunique-1.0-0 (1.1.6-5 Ubuntu:16.04/xenial [amd64])
Inst libvte-common (1:0.28.2-5ubuntu3 Ubuntu:16.04/xenial [all])
Inst libvte9 (1:0.28.2-5ubuntu3 Ubuntu:16.04/xenial [amd64])
Inst libwnck-common (1:2.30.7-5ubuntu1.1 Ubuntu:16.04/xenial-updates [all])
Inst libwnck22 (1:2.30.7-5ubuntu1.1 Ubuntu:16.04/xenial-updates [amd64])
Inst libxfce4util-bin (4.12.1-2 Ubuntu:16.04/xenial [amd64])
Inst mousepad (0.4.0-3ubuntu1 Ubuntu:16.04/xenial [amd64])
Inst thunar (1.6.11-0ubuntu0.16.04.2 Ubuntu:16.04/xenial-updates [amd64])
Inst thunar-archive-plugin (0.3.1-4 Ubuntu:16.04/xenial [amd64])
Inst thunar-media-tags-plugin (0.2.1-1 Ubuntu:16.04/xenial [amd64])
Inst thunar-volman (0.8.1-2 Ubuntu:16.04/xenial [amd64])
Inst tumbler-common (0.1.31-2build2 Ubuntu:16.04/xenial [all])
Inst tumbler (0.1.31-2build2 Ubuntu:16.04/xenial [amd64])
Inst xfburn (0.5.4-1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-artwork (0.1.1a~git+20110420-1 Ubuntu:16.04/xenial [all])
Inst xfce4-panel (4.12.0-3ubuntu2 Ubuntu:16.04/xenial [amd64])
Inst xfce4-battery-plugin (1.0.5-4build1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-clipman (2:1.2.6-1build1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-clipman-plugin (2:1.2.6-1build1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-cpufreq-plugin (1.1.2-1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-cpugraph-plugin (1.0.5-1build1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-datetime-plugin (0.6.2-2ubuntu2 Ubuntu:16.04/xenial [amd64])
Inst xfce4-dict (0.7.1-1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-diskperf-plugin (2.5.5-1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-fsguard-plugin (1.0.2-1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-genmon-plugin (3.4.0-2build1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-mailwatch-plugin (1.2.0-2ubuntu2 Ubuntu:16.04/xenial [amd64])
Inst xfce4-mount-plugin (0.6.7-1build1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-netload-plugin (1.2.4-1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-notes (1.8.1-1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-notes-plugin (1.8.1-1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-places-plugin (1.7.0-3 Ubuntu:16.04/xenial [amd64])
Inst xfce4-sensors-plugin (1.2.6-1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-smartbookmark-plugin (0.4.6-2 Ubuntu:16.04/xenial [amd64])
Inst xfce4-systemload-plugin (1:1.1.2-0ubuntu2 Ubuntu:16.04/xenial [amd64])
Inst xfce4-timer-plugin (1.6.0-1build1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-verve-plugin (1.1.0-1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-wavelan-plugin (0.5.12-1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-weather-plugin (0.8.9-0ubuntu0.16.04.1 Ubuntu:16.04/xenial-updates [amd64])
Inst xfce4-whiskermenu-plugin (1.5.1-1ubuntu1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-xkb-plugin (1:0.7.1-2 Ubuntu:16.04/xenial [amd64])
Inst ristretto (0.8.0-1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-screenshooter (1.8.2-2 Ubuntu:16.04/xenial [amd64])
Inst xfce4-taskmanager (1.1.0-1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-terminal (0.6.3-2ubuntu1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-goodies (4.12.1 Ubuntu:16.04/xenial [amd64])
Inst xfce4-power-manager-data (1.4.4-4ubuntu2 Ubuntu:16.04/xenial [all])
Inst xfce4-power-manager (1.4.4-4ubuntu2 Ubuntu:16.04/xenial [amd64])
Inst xfce4-power-manager-plugins (1.4.4-4ubuntu2 Ubuntu:16.04/xenial [amd64])
Inst hddtemp (0.3-beta15-52 Ubuntu:16.04/xenial [amd64])
Inst lm-sensors (1:3.4.0-2 Ubuntu:16.04/xenial [amd64])
Conf libxfce4util-common (4.12.1-2 Ubuntu:16.04/xenial [all])
Conf libxfce4util7 (4.12.1-2 Ubuntu:16.04/xenial [amd64])
Conf xfconf (4.12.0-2 Ubuntu:16.04/xenial [amd64])
Conf libxfconf-0-2 (4.12.0-2 Ubuntu:16.04/xenial [amd64])
Conf libxfce4ui-common (4.12.1-2 Ubuntu:16.04/xenial [all])
Conf libxfce4ui-1-0 (4.12.1-2 Ubuntu:16.04/xenial [amd64])
Conf libgarcon-common (0.4.0-2 Ubuntu:16.04/xenial [all])
Conf libgarcon-1-0 (0.4.0-2 Ubuntu:16.04/xenial [amd64])
Conf libexo-common (0.10.7-1 Ubuntu:16.04/xenial [all])
Conf libexo-helpers (0.10.7-1 Ubuntu:16.04/xenial [amd64])
Conf libexo-1-0 (0.10.7-1 Ubuntu:16.04/xenial [amd64])
Conf exo-utils (0.10.7-1 Ubuntu:16.04/xenial [amd64])
Conf libtagc0 (1.9.1-2.4ubuntu1 Ubuntu:16.04/xenial [amd64])
Conf thunar-data (1.6.11-0ubuntu0.16.04.2 Ubuntu:16.04/xenial-updates [all])
Conf libthunarx-2-0 (1.6.11-0ubuntu0.16.04.2 Ubuntu:16.04/xenial-updates [amd64])
Conf libtumbler-1-0 (0.1.31-2build2 Ubuntu:16.04/xenial [amd64])
Conf libunique-1.0-0 (1.1.6-5 Ubuntu:16.04/xenial [amd64])
Conf libvte-common (1:0.28.2-5ubuntu3 Ubuntu:16.04/xenial [all])
Conf libvte9 (1:0.28.2-5ubuntu3 Ubuntu:16.04/xenial [amd64])
Conf libwnck-common (1:2.30.7-5ubuntu1.1 Ubuntu:16.04/xenial-updates [all])
Conf libwnck22 (1:2.30.7-5ubuntu1.1 Ubuntu:16.04/xenial-updates [amd64])
Conf libxfce4util-bin (4.12.1-2 Ubuntu:16.04/xenial [amd64])
Conf mousepad (0.4.0-3ubuntu1 Ubuntu:16.04/xenial [amd64])
Conf thunar (1.6.11-0ubuntu0.16.04.2 Ubuntu:16.04/xenial-updates [amd64])
Conf thunar-archive-plugin (0.3.1-4 Ubuntu:16.04/xenial [amd64])
Conf thunar-media-tags-plugin (0.2.1-1 Ubuntu:16.04/xenial [amd64])
Conf thunar-volman (0.8.1-2 Ubuntu:16.04/xenial [amd64])
Conf tumbler-common (0.1.31-2build2 Ubuntu:16.04/xenial [all])
Conf tumbler (0.1.31-2build2 Ubuntu:16.04/xenial [amd64])
Conf xfburn (0.5.4-1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-artwork (0.1.1a~git+20110420-1 Ubuntu:16.04/xenial [all])
Conf xfce4-panel (4.12.0-3ubuntu2 Ubuntu:16.04/xenial [amd64])
Conf xfce4-battery-plugin (1.0.5-4build1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-clipman (2:1.2.6-1build1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-clipman-plugin (2:1.2.6-1build1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-cpufreq-plugin (1.1.2-1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-cpugraph-plugin (1.0.5-1build1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-datetime-plugin (0.6.2-2ubuntu2 Ubuntu:16.04/xenial [amd64])
Conf xfce4-dict (0.7.1-1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-diskperf-plugin (2.5.5-1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-fsguard-plugin (1.0.2-1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-genmon-plugin (3.4.0-2build1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-mailwatch-plugin (1.2.0-2ubuntu2 Ubuntu:16.04/xenial [amd64])
Conf xfce4-mount-plugin (0.6.7-1build1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-netload-plugin (1.2.4-1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-notes (1.8.1-1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-notes-plugin (1.8.1-1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-places-plugin (1.7.0-3 Ubuntu:16.04/xenial [amd64])
Conf xfce4-sensors-plugin (1.2.6-1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-smartbookmark-plugin (0.4.6-2 Ubuntu:16.04/xenial [amd64])
Conf xfce4-systemload-plugin (1:1.1.2-0ubuntu2 Ubuntu:16.04/xenial [amd64])
Conf xfce4-timer-plugin (1.6.0-1build1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-verve-plugin (1.1.0-1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-wavelan-plugin (0.5.12-1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-weather-plugin (0.8.9-0ubuntu0.16.04.1 Ubuntu:16.04/xenial-updates [amd64])
Conf xfce4-whiskermenu-plugin (1.5.1-1ubuntu1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-xkb-plugin (1:0.7.1-2 Ubuntu:16.04/xenial [amd64])
Conf ristretto (0.8.0-1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-screenshooter (1.8.2-2 Ubuntu:16.04/xenial [amd64])
Conf xfce4-taskmanager (1.1.0-1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-terminal (0.6.3-2ubuntu1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-goodies (4.12.1 Ubuntu:16.04/xenial [amd64])
Conf xfce4-power-manager-data (1.4.4-4ubuntu2 Ubuntu:16.04/xenial [all])
Conf xfce4-power-manager (1.4.4-4ubuntu2 Ubuntu:16.04/xenial [amd64])
Conf xfce4-power-manager-plugins (1.4.4-4ubuntu2 Ubuntu:16.04/xenial [amd64])
Conf hddtemp (0.3-beta15-52 Ubuntu:16.04/xenial [amd64])
Conf lm-sensors (1:3.4.0-2 Ubuntu:16.04/xenial [amd64])
Em nenhum lugar disso é mencionado Midori.
Agora, se você tentou instalar os pacotes de pacotes XFCE completos e não apenas o pacote goodies, o Midori pode ser incluído. (no entanto, ele não faz parte dos conjuntos de pacotes padrão em nenhum lugar, nem mesmo nos pacotes de pacotes do Xubuntu por padrão, a menos que seja puxado como sua própria dependência)