Attach images already in media library

I’ve got this issue: there’s no possibility to attach to current post any image already uploaded in media library and previously attached to another post. That’s annoying, because either I upload the same file again or I have to get id from the other post, attach all images from it and then in case remove the ones I don’t want to be attached to the current post. Am i missing anything? I think I could use this function in previous WordPress versions… any suggestion will be greatly appreciated. thanx.

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