No light/dark switch on Linux with default theme

[neitsab]

Hi all,

The tldr of my question is: does Ghostty's default theme support switching between light and dark mode on Linux? From my experiments it appears not. Can someone confirm?

Details:

I've just installed Ghostty on Arch Linux from the official repos, and I am using it in a regular GNOME Wayland session.

When I open Ghostty, its default theme is dark despite my system settings being on Default (Light).

Using GNOME system menu toggle to switch between Light and Dark mode doesn't change things: Ghostty's interface remains dark. The following line gets printed in my logs:

mutter-x11-fram[7439]: Using GtkSettings:gtk-application-prefer-dark-theme with libadwaita is unsupported. Please use AdwStyleManager:color-scheme instead.

By contrast, Ptyxis correctly alternates between light and dark theme (fwiw Ptyxis is installed as a Flatpak, while Ghostty is natively installed).

I haven't found any information regarding what Ghostty uses as its default theme, be it in its doc, online or here in the repo, nor was I able to find it in ghostty +list-themes. On my system the colors I see don't match the theme called "Builtin Dark" at least.

Here's the result of ghostty +show-config:

command = /usr/bin/zsh
click-repeat-interval = 500
auto-update-channel = stable

(My config file so far was empty).

https://ghostty.org/docs/config/reference#window-theme doesn't mention which value is the default (auto? system?); I've tried window-theme=auto, window-theme=system and window-theme=light while saving and reloading the config between each, to no avail.

However, the theme does toggle between light and dark when I use a theme=light:catppuccin-latte,dark:catppuccin-frappe for example.

So, am I right thinking the default theme doesn't support light/dark switching on Linux? If so could this be added to the documentation, because reading https://ghostty.org/docs/about#feature-rich and https://ghostty.org/docs/config#zero-configuration-philosophy had me believe it would support it with its default theme/config.

Thanks for reading, cheers!

[rhodes-b]

You need to configure ghostty to switch between a system dark and light theme it does not do this by default

https://ghostty.org/docs/config/reference#theme
reading the docs specifically about theme I think it makes that clear

To specify a different theme for light and dark mode, use the following syntax: light:theme-name,dark:theme-name. For example: light:rose-pine-dawn,dark:rose-pine. Whitespace around all values are trimmed and order of light and dark does not matter. Both light and dark must be specified in this form. In this form, the theme used will be based on the current desktop environment theme.

you should also see that ghostty +show-config --default does not have this by default

[neitsab]

Thanks for your confirmation and tip to verify it myself.

I had read the documentation you cite, but to me it doesn't make clear whether this happens for the default theme or not, which actually as the output of the command you shared shows, doesn't even have a name (ghostty +show-config --default | grep theme).

I'll try to plead for a light/dark switching default theme in the relevant "Zero configuration" discussion. edit: link to the plea

Cheers!