Web Messaging SDK configuration not applying custom colors via JSON payload

We are instrumenting the Genesys Cloud Web Messaging widget to feed engagement metrics into New Relic. As part of the setup, we need to brand the widget to match our client’s portal. I’m trying to pass the configuration object directly to the genesyscloud-messaging script tag to set the launcher position and primary color.

Here is the configuration JSON I’m passing:

window.GenesysCloudMessaging = {
 deploymentId: '550e8400-e29b-41d4-a716-446655440000',
 config: {
 launcherPosition: 'bottom-right',
 theme: {
 primaryColor: '#FF0000',
 launcherColor: '#000000'
 }
 }
};

The widget loads successfully. The deploymentId is valid and authenticated via the standard OAuth flow we have in place. However, the UI ignores the primaryColor and launcherPosition settings. It defaults to the blue theme set in the Genesys Cloud admin console.

I’ve verified the deployment ID in the GC portal. The admin settings show “Use default branding” is unchecked, but the specific color values I’m passing via the SDK config aren’t sticking. The network tab shows the initial GET request to /api/v2/messaging/deployments/{deploymentId} returns a 200 OK, but the payload doesn’t seem to merge with my client-side config.

Is there a specific flag I’m missing in the JSON payload? Or does the SDK override client-side config if the deployment has branding defined in the admin UI? I need to force the red color for this specific A/B test group.