Set application to "always on top"

Question

I am using Ubuntu 23.10 and I would like to set an application, in my case CuteCom Serial Monitor, to be always on top. At the moment if my IDE is fullscreen I have to launch CuteCom from the dash and then after I return to the IDE and make some changes I have to relaunch Cutecom from the dash again.

If this is possible I can imagine it being useful for other applications too.

Answer 1

Just right-click on the titlebar of the window you want to keep on top and select Always on Top from the menu.

Alternatively, if you prefer to not use the mouse, you can press Alt+Super and use the up and down arrows to select Always on Top.

Answer 2

From command line? If so, you need wmctrl.
In it's most simple form:

xwin=$(xwininfo | grep -oP 'Window id: \K0x[0-9a-f]+'); wmctrl -i -r "$xwin" -b add,above

This could serve as a GUI version.
These are the dependencies you will need to install.

sudo apt-get install xdotool xprop wmctrl yad xbindkeys

#!/bin/bash

about_dialog() {
yad --window-icon="help-faq" --title="About" --on-top --borders=10 --center --skip-taskbar --image="preferences-system-windows" --buttons-layout="center" --text-align=center --text="Always On Top!\n\nChange selected window's 'state' from\n'Below' to 'Above' & Vice-versa.\n" --button=Close!application-exit!:0
}
export -f about_dialog
set_keybinding() {
if [ ! -f ~/.ontop_tray_xkbrc ]; then
current_binding='[none]'
else
current_binding=$(sed '2q;d' ~/.ontop_tray_xkbrc)
fi
remove_button='rm ~/.ontop_tray_xkbrc; echo "\"bash -c 'toggle_gnome'\"" > ~/.ontop_tray_xkbrc && xdotool windowkill window="cat /tmp/xwin_id_xkb" && bash -c set_keybinding'
show_current=$(echo "$current_binding")

yad --window-icon="input-keyboard" --borders="15" --on-top --skip-taskbar --title="Key Binding" \
    --text-align="center" --buttons-layout="center" --text="Current Binding\n$show_current\n" \
    --separator=" " --item-separator=" " --print-xid="/tmp/xwin_id_xkb" --form  \
    --field="Hold 1:":CB "Ctrl Alt Shift" \
    --field="Hold 2:":CB "Shift Ctrl Alt" \
    --field="Action:":entry "T" \
    --field=Remove-Binding:BTN "bash -c '$remove_button'" \
    --button=Confirm:0 \
    --button=Cancel:1 > /tmp/entries

if [ $? -ne 0 ]; then
    exit 1
fi

entries=$(cut -d'|' -f1 < /tmp/entries)

f1=$(echo "$entries" | awk '{print $1}')
f2=$(echo "$entries" | awk '{print $2}')
f3=$(echo "$entries" | awk '{print $3}')

key_combo=$(echo "$f1+$f2+$f3" | tr ' ' '+')

if [ ! -f ~/.ontop_tray_xkbrc ]; then
    echo "\"bash -c 'toggle_gnome'\"" > ~/.ontop_tray_xkbrc
fi

echo "$key_combo" > ~/.ontop_tray_xkbrc

# Restart xbindkeys
killall xbindkeys 2> /dev/null
xbindkeys --file ~/.ontop_tray_xkbrc
}
export -f set_keybinding
tmp_error() {
yad --skip-taskbar --on-top --window-icon="gtk-error" --title="Write Error" --image="gtk-error" 

--button="Quit":1 

--text="Unable to write to /tmp\nCheck permissions for $USER."
exit 1
}
export -f tmp_error
error_control() {
Workaround:   Clicking OSK's enter-key will cause crosshair failure.
wmctrl, xdotool & xprop—all fail with 'onboard' OSK.
yad --skip-taskbar --on-top --window-icon="dialog-question" --title="Retry?" --image="dialog-question" \
    --button="Try Again":0 \
    --button="Quit":1 \
    --text="Failed to focus on the window.\nDo you want to retry?" \

response=$?

if [ $response -eq 0 ]; then
            select_window
else
    exit 1
fi
}
export -f error_control
select_window() {
xdotool selectwindow > /tmp/xwin_id
    if [ $? -ne 0 ]; then
        error_control
    fi

    if [ ! -f /tmp/xwin_id ]; then
    tmp_error
    fi

    wmctrl -i -r "$(sed '1q;d' /tmp/xwin_id)" -b add,above
}
export -f select_window
select_new() {
wmctrl -i -r $(sed '1q;d' /tmp/xwin_id) -b remove,above
rm /tmp/xwin_id
select_window
}
export -f select_new
toggle_gnome() {
toggle_xwin_id=$(</tmp/xwin_id)
xprop -id "$toggle_xwin_id" > /tmp/xwin_state
check_state=$(cat /tmp/xwin_state | grep -q "_NET_WM_STATE(ATOM) = _NET_WM_STATE_ABOVE")
if [ $? -eq 0 ]; then
    wmctrl -i -r &quot;$toggle_xwin_id&quot; -b remove,above
else
    wmctrl -i -r &quot;$toggle_xwin_id&quot; -b add,above
fi
}
export -f toggle_gnome
select_window
Tray Icon & Menu
yad --notification --skip-taskbar --image="go-top" 

--command="bash -c 'about_dialog'" 

--menu=" Toggle !bash -c 'toggle_gnome' 

| Select !bash -c 'echo "1" >> /tmp/xwin_id; select_new' 

| Keybind !bash -c 'set_keybinding' 

| Exit !bash -c 'wmctrl -i -r $(sed '1q;d' /tmp/xwin_id) -b remove,above && killall yad'" 

--text="Always On Top!"
exit 0

It will prompt to choose a window. Right click the tray icon to: Toggle (on/off), Select different "Always On Top" window & Keybind to set hotkey for toggling.

Save to: ontop_tray_icon.sh
Change mode to executable: chmod +x ontop_tray_icon.sh
Usage: ./ontop_tray_icon.sh