I can't seem to be able to re-create this problem. I've uploaded a test CSV and a PDF file to a test server, and using this mime type:
..I'm only getting the PDF file as a result, so I don't know yet.
– What mime types do you have entered into the field?
– Do you get any other attachment types as results?
– Can you please add temporary FTP and login access, so I can take a look at the issue?
I've investigated the attachment search core code, but unfortunately I don't see any mistakes there, so I don't know what can be causing this. Maybe the mime type of the CSV files was wrongly recognized by wordpress by accident?Best,
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