I had the ability to upload images using the single image field. I needed another one, but when added it does not work, A click results in no action. If I remove the image from the first single image field and try to add a new image it is also unresponsive.
I import the JSON file to my demo site and I can upload a single image as well. On your site, it could be a conflicting issue with another plugin or theme. You can try to deactivate all plugins except Meta Box, MB extension plugins, switch to a WordPress theme and check the issue again.
Sent the details through however it 'seems' to be a rogue chrome extension causing the issue. I will report back if it is something different, thank you.
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