Vim docs have light background with dark theme in flatpak zeal

[Praful]

I'm using flatpak zeal 0.9.0 in Linux Mint 22.3 Cinnamon.

I have a dark OS theme. The docs in Zeal for Python have a dark background. The vim docs have a light background.

I'm using the following CSS to workaround the issue:

html,
body {
  background-color: var(--bg0) !important;
  color: var(--fg1) !important;
}

When I was using zeal installed by apt, the vim docs background was correct. Therefore I assume this is a flatpak+zeal issue.

[TheJudge26]

The discrepancy usually happens because the Flatpak sandbox isolates the application from your host system's native themes, Qt platform styles, or system-wide font/CSS configurations.

When you used the apt package, Zeal likely inherited system environment variables or theme plugins (qt5-style-plugins / GTK integration) that correctly informed the embedded WebKit/Blink engine about your dark theme preferences, allowing docsets with explicit or default light background rules to adapt. In the Flatpak build, those host-level style bridges aren't automatically exposed to the containerized web view unless explicitly configured

[trollixx]

See #1966.