White backgrounds appearing unexpectedly with Horizon theme

AI-generated summary

donaldsoncd reported an issue where parts of their Discourse forum using the Horizon theme, such as the composer and main interface, suddenly appeared with a white background instead of the intended cream color (#FFFDF1). This unexpected behavior occurred for their admin account but not for a test user account. Although both accounts were in light mode with a custom color palette, the issue persisted even after disabling the new composer redesign feature.

Using browser developer tools, donaldsoncd discovered that the CSS variable --d-content-background was being calculated as nearly white rather than the expected palette color. Manually overriding this variable with #FFFDF1 resolved the visual glitch, but the user is unsure whether the root cause is a bug in the Horizon theme, a recent Discourse update, or a specific configuration issue. They are seeking assistance from the community to identify and permanently fix the underlying problem.

Hello!

Today, I noticed that some areas of my Discourse forum have suddenly started appearing white instead of my usual cream background. This includes the composer and parts of the main interface.

Examples from my main admin account:

Here is the issue not occurring with test user account:

I’m using the Horizon theme with a custom color palette and using light mode with both accounts. Here’s screenshots:

I initially thought the issue was related to the new composer redesign, but disabling that didn’t resolve it.

I’m not a developer, so I’m unsure whether this is a bug in Horizon, a recent Discourse change, or something specific to my configuration.

With some AI help, I used Chrome’s developer tools to investigate. It looks like the CSS variable --d-content-background is being calculated as nearly white, even though my palette’s background color is #FFFDF1. Temporarily changing that variable to #FFFDF1 fixed the appearance.

Has anyone else encountered this and can you help me resolve?