Favicon test app

For seeing which applications use which icons in which contexts (because nothing is ever simple).

Icon reference

Icon File used / dimensions
A red square with '16' written in white. favicon.ico (16×16)
A red square with '32' written in white. favicon.ico (32×32)
A red square with '48' written in white. favicon.ico (48×48)
An orange square with 'SVG' written in white. favicon.svg (variable)
A magenta square with '180' written in white. icon-180.png (180×180)
A blue square with '192' written in white. icon-192.png (192×192)
A green square with '512' written in white. icon-512.png (512×512)
A black square with the letter 'M' transparently punched through it. icon-mask.svg (variable)