I submited the prior bug request Dired dired-clean-up-after-deletion
bug.

A feature enhancement that is related to this is that I would like to be
able to set
the file extensions that would automatically be deleted. Then for the
other file extensions confirm before deleting the buffers. I see
possiblyl changing dired-clean-confirm-killing-deleted-buffers to
allowing three differnt options. One is nil meaning don't ask and
automatically kill everything. One is t meaning confirm all buffers. The
last is a list like '(.txt .pdf)) that will allow these extensions to
automatically be killed but all others it will ask. But the problem with
this is the dired and sub-directory killing part. If you specify a list,
I think there needs a seperate variable that you can control the dired
buffer killing from the regular buffer killing.