Hi @modifly
Very cool!
However, it will not be possible to add this to the ACF image popup at the moment.
The ACF media popup does not instantiate the sidebar or ‘states’ needed for your retina uploader to work.
I’m sorry about this dead end, but not much I can do to help.
Perhaps you could take the image field and create your own with a slightly modifies JS to allow for your sidebar / state?
Good luck!
Thanks
E
