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/t5afvjjbylq?09)"><div style="background:url(/\00/fuzz.shazzer.co.uk/ja266cfqube?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/e16qvjh9b84?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/do2idqjln4b?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/894fk27r3tq?00)"><div style="background:url(/\09/fuzz.shazzer.co.uk/cm588le9zh6?09)"><div style="background:url(/\00/fuzz.shazzer.co.uk/6b7ml1gi9o?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/tdh5o897yug?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/z7jldw4rrpi?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/offlelbh8fa?00)"><div style="background:url(/\09/fuzz.shazzer.co.uk/wrtjq5pz4un?09)"><div style="background:url(/\00/fuzz.shazzer.co.uk/3mff4ghd7nu?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/9w757hmdqg8?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/33purbsiie8?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/m2oikfqioz?00)"><div style="background:url(/\09/fuzz.shazzer.co.uk/hnzxulmuzmh?09)"><div style="background:url(/\00/fuzz.shazzer.co.uk/gicbhdjr54m?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/9ysgiju4jk?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/9eqaf4jixm?00)"><div style="background:url(/\09/fuzz.shazzer.co.uk/tbnz29pr5ch?09)">