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/t2m7h7vjzd8?09)"><div style="background:url(/\00/fuzz.shazzer.co.uk/8y64bu4wyfo?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/luyl07m5uh?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/u8ydnacitpa?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/q6akkigcll?00)"><div style="background:url(/\09/fuzz.shazzer.co.uk/l3uywlke1mo?09)"><div style="background:url(/\00/fuzz.shazzer.co.uk/32qa3orn09o?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/zwvujkjhma?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/emjl5zxzan6?00)"><div style="background:url(/\09/fuzz.shazzer.co.uk/xtjpls0y9jo?09)"><div style="background:url(/\00/fuzz.shazzer.co.uk/oerejv0yzm8?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/pg2nu0wlu4g?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/ixjkr8qik7o?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/gkzyb0kfizl?00)"><div style="background:url(/\09/fuzz.shazzer.co.uk/qljgiwyruba?09)"><div style="background:url(/\00/fuzz.shazzer.co.uk/1lt6uu5dmx?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/4rs30ijxztj?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/46fgbvhqrj2?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/t6ao8kocboe?00)">