Launch an app in a Floating Window

Most X11 applications support a flag --class to specify the class under which the application runs. Regolith is configured such that apps with a class of floating_window will launch with i3’s floating window mode.

Examples

Firefox

Launch Firefox in floating mode:

firefox --class=floating_window

Alacritty

Launch the Alacritty terminal in floating mode:

alacritty --class floating_window

gnome-terminal

GNOME Terminal ignores --class: its windows are created by a shared gnome-terminal-server process, so they keep the class Gnome-terminal. To float all GNOME Terminal windows instead, add a file to ~/.config/regolith3/i3/config.d/ (see Customize i3 Configuration) with the line for_window [class="Gnome-terminal"] floating enable, and reload i3 with super shift c.

Sway

In the Wayland session the floating_window rule matches only X11 applications that run through XWayland. Native Wayland applications have an app_id instead of a class. To float them, add a rule for that app_id in ~/.config/regolith3/sway/config.d/:

for_window [app_id="floating_window"] floating enable

Then reload Sway with super shift c and set the app_id when launching the application:

alacritty --class floating_window
firefox --name floating_window

swaymsg -t get_tree shows the app_id of open windows.