In Salesforce, the Salesforce Lightning Design System 2 (SLDS 2) is the updated theming framework used for custom themes in Starter orgs. SLDS 2 provides improved visual design capabilities compared to the original SLDS theming system.
When SLDS 2 became generally available, the ability to configure a custom global header background color — which was available during the SLDS 2 beta period — was removed from the feature set.
In some cases, global header background color selections made for SLDS 2 themes caused accessibility issues when dark mode was enabled. To ensure all users have an accessible experience, Salesforce removed this function from SLDS 2 custom themes. Salesforce is exploring ways to return this functionality in a way that maintains accessibility compliance.
Dark mode is now available in beta for SLDS 2 themes in Starter orgs. Salesforce continues to evaluate how to restore global header background color customization while maintaining accessibility standards for dark mode users.
To vote for restoring this functionality, see the IdeaExchange topic: Enable Custom Global Header Background Color in Themes / Branding — SLDS 2 Support
If you need to customize your org's header appearance, consider these alternatives:
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