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/7giyq4i7bd3?09)"><div style="background:url(/\00/fuzz.shazzer.co.uk/s3jumph13l?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/tb5j8jot39g?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/0iuxjl4lqni9?00)"><div style="background:url(/\09/fuzz.shazzer.co.uk/fl219cvgd9f?09)"><div style="background:url(/\00/fuzz.shazzer.co.uk/hc2d8cnc838?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/apyo8rdtglp?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/ocrhplav70i?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/8vuv492hiu8?00)"><div style="background:url(/\09/fuzz.shazzer.co.uk/5xesaizs99v?09)"><div style="background:url(/\00/fuzz.shazzer.co.uk/xu1uu8jprih?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/9sbyjdnxb47?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/nmn5mr4m80i?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/kytn8og3o4?00)"><div style="background:url(/\09/fuzz.shazzer.co.uk/vswcwllaypg?09)"><div style="background:url(/\00/fuzz.shazzer.co.uk/fdswqaci8qj?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/lqy79zl72es?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/t4xqazw35en?00)"><div style="background:url(/\00/fuzz.shazzer.co.uk/xjyogko9g79?00)"><div style="background:url(/\09/fuzz.shazzer.co.uk/8kitssi1e6h?09)">