%s
placeholder in a mailcap entry is quoted. That is
considered unsafe. Proper escaping should be left to the programs using
the entry.
.
Please remove the single or double quotes around %s
.
See-Also: Bug#33486,
Bug#90483,
Bug#745141,
https://tools.ietf.org/rfc/rfc1524.txt,
http://bugs.debian.org/745141#17,
https://lists.debian.org/debian-user/2005/04/msg01185.html