Tests which escapes cause an external request in-between forward slashes within a CSS URL scheme for background images.
<div style="background:url(/\$[hex2]/fuzz.shazzer.co.uk/$[rand]?$[hex2])"><div style="background:url(/\09/fuzz.shazzer.co.uk/0gkn78tu0885?09)"><div style="background:url(/\00/fuzz.shazzer.co.uk/y3dais6vij?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/ra6c44hnzo?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/urmetrf6a?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/u3j2dyb2n9g?00)"><div style="background:url(/\09/fuzz.shazzer.co.uk/qoez07kyiah?09)"><div style="background:url(/\00/fuzz.shazzer.co.uk/0ybiuoflaxge?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/5luwzgq00it?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/2r1979alydk?00)"><div style="background:url(/\09/fuzz.shazzer.co.uk/9dign7zyizk?09)"><div style="background:url(/\00/fuzz.shazzer.co.uk/bseerd9lwre?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/02n29v1khb2i?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/xeiqi9krsdj?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/u9vu5ryxcba?00)"><div style="background:url(/\09/fuzz.shazzer.co.uk/i5rrkzcluhf?09)"><div style="background:url(/\00/fuzz.shazzer.co.uk/q3q8m5ylov?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/1xyubd1zusf?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/5rn38kutz3p?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/8slyth1s72a?00)"><div style="background:url(/\09/fuzz.shazzer.co.uk/1jzbg9038k6?09)">