While waiting for the bug report to get resolved I found a workaround using custom:card-modder
- type: picture-elements
image: /local/camera_bg.png
elements:
- type: custom:card-modder
style:
width: 100%
height: 100%
top: 50%
left: 25%
card:
type: picture-entity
entity: camera.test_camera
camera_view: live
show_name: false
show_state: false