My default sort is modified date. I noticed that an image which I copied into a test folder always sorts to the top, as shown. Further tests show that it stays at the top regardless of what column I sort by, ascending or descending. It is somehow locked to the top of the list. I have confirmed that the folder format comes from the User Default which works perfectly everywhere else.
Is this caused by something I have done inadvertently? I am not aware of any mechanism to lock something to the top and the User Default format doesn't offer any clues. The same file sorts correctly in the (Downloads) folder I copied it from.