diff --git a/src/mime/type.go b/src/mime/type.go
index ac7b0447da3..58cc22fdb01 100644
--- a/src/mime/type.go
+++ b/src/mime/type.go
@@ -156,6 +156,7 @@ func initMime() {
 //	/etc/mime.types
 //	/etc/apache2/mime.types
 //	/etc/apache/mime.types
+//	/etc/httpd/conf/mime.types
 //
 // On Windows, MIME types are extracted from the registry.
 //
@@ -197,6 +198,19 @@ func TypeByExtension(ext string) string {
 // type typ. The returned extensions will each begin with a leading dot, as in
 // ".html". When typ has no associated extensions, ExtensionsByType returns an
 // nil slice.
+//
+// The built-in table is small but on unix it is augmented by the local
+// system's MIME-info database or mime.types file(s) if available under one or
+// more of these names:
+//
+//	/usr/local/share/mime/globs2
+//	/usr/share/mime/globs2
+//	/etc/mime.types
+//	/etc/apache2/mime.types
+//	/etc/apache/mime.types
+//	/etc/httpd/conf/mime.types
+//
+// On Windows, extensions are extracted from the registry.
 func ExtensionsByType(typ string) ([]string, error) {
 	justType, _, err := ParseMediaType(typ)
 	if err != nil {