How to change the default image of a mobile guest user?

 You may change the default guest user for your mobile group chat to any image by using your own image URL.

.user-image,
.message-user-image {
width: 0 !important;
padding-right: 32px;
background-image: url("//rumbletalk-images-upload.s3.amazonaws.com/cc244d13c0e7e7bb6c4b63830314dc61/1444667334-usericon-blue.png");
background-repeat: no-repeat;
}



To know how to edit the mobile CSS, refer to this link.