Light variant of dynamic themes applied by default despite system preferring dark theme #12278

System Information

• fish version: 4.3.2
• Operating system: Linux
  • Distribution: Arch Linux
  • Desktop environment: KDE Plasma

Issue Description

Despite me having set my operating system to prefer dark theme, and my fish_terminal_color_theme variant outputs "dark" when used with the echo command, when I choose a dynamic theme that includes both light and dark variants for fish 4.3, fish will apply the light variant by default.

I have tried fish without third-party customizations by running sh -c 'env HOME=$(mktemp -d) XDG_CONFIG_HOME= XDG_DATA_DIRS= fish'. When I run fish_config theme choose THEME to set a dynamic theme, the light variant is applied by default.

I have noticed that when I run fish_config and launch the web-based configuration interface and select a dynamic theme, the preview section shows the light variant instead.

Similarly, if I set fish_config theme choose THEME in my fish configuration file, when I restart a fish session, the light variant will be applied instead of the dark variant.

I work around this issue by passing the --color-theme=dark argument to fish_config theme choose THEME in my fish config file, but ideally, fish would apply the dark variant by default if the user has set the system to prefer dark themes.

Steps to Reproduce the Issue

1. Set the operating system to prefer dark theme.
2. Start the fish shell with a terminal emulator.
3. Run the command echo $fish_terminal_color_theme to confirm it outputs dark.
4. Choose a dynamic theme by running fish_config theme choose THEME. For example, fish_config theme choose tomorrow.
5. Run fish_config theme show to display available fish themes.
6. Type a command and take note if the colour scheme is the light or dark variant.

asciinema Recording

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