In engagement messenger how do I modify the default font

[Harrys09]

 

In engagement messenger how do I modify the default font to a different one and how do I modify the background colour and tiles css?

[Maik Skoddow]

The only options I'm aware of can be seen at https://youtu.be/6UrvnvqMtVk?si=AjSiYJX1AwumFZvz&t=37