I figured out the trick, unselect “full size” and select “large”, it’s not exactly what i wanted but it’s something with it having an issue when admin “full size” is selected.
I know “large” maybe not an option for you as I am using larger images, but it’s how I worked around it. maybe you can select “medium” ?
GL
I’m having the exact same issue.
When i upload images through their “add image” button, it automatically resizes them down to 150x150px, I triple checked the URL , it’s definitely the plugin resizing the images on “save” / “update”