diff -up ikiwiki-3.20180105/t/img.t.orig ikiwiki-3.20180105/t/img.t
--- ikiwiki-3.20180105/t/img.t.orig	2018-01-31 16:59:14.456950056 +0100
+++ ikiwiki-3.20180105/t/img.t	2018-01-31 16:59:40.841694110 +0100
@@ -106,7 +106,7 @@ ok(! system(@command, '--set-yaml', 'img
 sub size($) {
 	my $filename = shift;
 	my $im = Image::Magick->new();
-	my $r = $im->Read(":$filename");
+	my $r = $im->Read("$filename");
 	return "no image: $r" if $r;
 	my $w = $im->Get("width");
 	my $h = $im->Get("height");