The web messenger in Freshchat also known as the conversations widget, is used to deliver a convenient and contextual conversational messaging experience for customers. You can customize the widget to match your brand.
For example, you can change the widget color from Admin > Web Messenger > Appearance. You could also use the below code snippet:
headerProperty: {
backgroundColor: '#FFFF00',
foregroundColor: '#333333',
backgroundImage: 'https://wchat.freshchat.com/assets/images/texture_background_1-bdc7191884a15871ed640bcb0635e7e7.png'
}