planemo serve does not display images in help section

Currently, planemo serve does not allow to preview the images in help section.
It would be good to be able to test if the path of the image is well formated and if the width/height need to be adjusted.
planemo serve should adapt this code:
https://github.com/galaxyproject/galaxy/blob/bac4736e054222b00a5c0c7bf4d952fa625ee718/lib/galaxy/webapps/galaxy/controllers/shed_tool_static.py#L21-L58
And copy the images to galaxy_root/static/images.
I don't know where this block should be included in the code as I don't really understand how planemo serve works.
Thanks