I guess I’m crazy, because the plugin seems to be working as desired now. I’m able to enable it on a per-site basis. I don’t know why it wasn’t working that way before. I won’t waste any more of your time. Thanks for the plugin!
Bump! Any word on if this behavior can be modified on a multi-site install?
Looks like it’s working to me. I see the image reloading at each breakpoint. I did notice that you may want to address the location of the post date. At smaller widths it gets cut off.