To clarify the issue – and you can go through these steps too –
– Upload an image/file to the media library
– create a new post and add that new file to the post using the image field
– save the post
– go to the media library and you will see that the file is not “attached” to the post
The issue is the same for new and existing posts. Hope that helps clarify it a bit more – let me know if you need more info.
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