+(eval-after-load "w3m"
+ '(let ((entries '(("application/pdf" "\\.pdf\\'" ("evince" file) nil)
+ ("application/x-pdf" "\\.pdf\\'" ("evince" file) nil))))
+ (dolist (e entries)
+ (setq w3m-content-type-alist
+ (cons e (remove* (car e) w3m-content-type-alist
+ :key #'car :test #'string=))))))
+