The question https://meta.stackexchange.com/q/345815/336163 (asked less than ten minutes ago) was closed as a duplicate less than five minutes ago, but it lacks any semblance of a duplicate target.
The header shows:
This question already exists:
The expected link to the duplicate target is missing.
Its timeline shows that it was closed by "Jenayah, Community♦" as "Duplicate of… " That's it, duplicate of....
What happened, and can we fix it?
I suspected that the duplicate target might simply have been deleted, but then I recognized the extremely short time between closure and now (not really enough time for others to get around to deleting), and also that one generally can't vote to delete a question that is a duplicate target - one instead gets a message that the question can't be deleted.
Another example of this happening: How can I reliably determine if a file is an image file?