Currently, the live chat (“messages”) feature only allows you to select an accent color. However, the accent color we chose causes the chat icon itself to become a dark blue, which clashes with our landing page color scheme.
Marcus from HubSpot eventually helped us figure out a way to change the icon to white which looks better (ticket 982958) but it would be much better to allow us to choose the color scheme explicitly. Or better yet, allow us to customize it with CSS to give us even more flexibility. (CSS from the Landing Page does not apply since it is inside an iframe.)