I'm using the Adaptable 1.8 on a Moodle 3.6.1 sandbox site
The course images on the dashboard have always been off. Larger than the container and not scaled.
On 3.5.X we used custom CSS to fix this but the code does not work on 3.6.1
CSS code:
.block_myoverview .myoverviewimg.courseimage {
background-position: center;
background-size: 80px;
width: 80px;
height: 80px;
}