When I change my GTK theme to the light theme, Qt reports that I am using a dark theme.

When I change my GTK theme to the dark theme, Qt also reports that I am using a dark theme.

After inspecting the platform theme code, I found that it determines the current light/dark mode by finding the sub-string `dark` inside the theme name. This approach is unsound. The light theme that I am using is called "Arc-Darker". It has a white background, but is called "darker" because the titlebar and menubar is black:

https://github.com/jnsh/arc-theme?tab=readme-ov-file#arc-is-available-in-four-variants

Because the theme name has the substring "dark", Qt assumes that it is a dark theme and reports this.