etc/proofgeneral-settings.el

proper find -mtime (file data) instead of -ctime (meta data);

;;; Options for Proof General
;;;
;;; Examples for sensible settings:

;; keep sources clean
(custom-set-variables '(indent-tabs-mode nil))

;; retain vital AltGr behaviour, e.g. on non-US Mac OS X
;(custom-set-variables '(ns-alternate-modifier 'none))

;; longer timeout for saving persistent session
;(custom-set-variables '(proof-shell-quit-timeout 60))