Aqui estão alguns atalhos de teclado que eu uso para o controle de janela no Lubuntu / LXDE. A primeira ligação é o que você está procurando, mas eu achei que você poderia encontrar as outras úteis também:
<!-- Keybindings for window tiling -->
<keybind key="C-W-Up"> # FullScreen
<action name="Maximize"/>
</keybind>
<keybind key="C-W-Down"> # MiddleScreen
<action name="UnmaximizeFull"/>
<action name="MoveResizeTo"><x>center</x><y>center</y><width>50%</width><height>50%</height></action>
</keybind>
<keybind key="C-W-Left"> # HalfLeftScreen
<action name="UnmaximizeFull"/>
<action name="MoveResizeTo"><x>0</x><y>0</y><height>100%</height><width>50%</width></action>
</keybind>
<keybind key="C-W-Right"> # HalfRightScreen
<action name="UnmaximizeFull"/>
<action name="MoveResizeTo"><x>-0</x><y>0</y><height>100%</height><width>50%</width></action>
</keybind>
<keybind key="C-W-1"> # UpperQuarterLeft
<action name="UnmaximizeFull"/>
<action name="MoveResizeTo"><x>0</x><y>0</y><height>50%</height><width>50%</width></action>
</keybind>
<keybind key="C-W-2"> # LowerQuarterLeft
<action name="UnmaximizeFull"/>
<action name="MoveResizeTo"><x>0</x><y>-0</y><height>50%</height><width>50%</width></action>
</keybind>
<keybind key="C-W-3"> # LowerQuarterRight
<action name="UnmaximizeFull"/>
<action name="MoveResizeTo"><x>-0</x><y>-0</y><height>50%</height><width>50%</width></action>
</keybind>
<keybind key="C-W-4"> # UpperQuarterRight
<action name="UnmaximizeFull"/>
<action name="MoveResizeTo"><x>-0</x><y>0</y><height>50%</height><width>50%</width></action>
</keybind>
Você pode precisar ajustar as porcentagens com base no uso ou não de um painel.
C-W-Up
significa CTRL + SUPER + ↑