Excerpt
A good test string for Unicode support in general is the following: Iñtërnâtiônàlizætiøn☃?. Its first 20 symbols are in the range from U+0000 to U+00FF, then there’s a symbol in the range from U+0100 to U+FFFF, and finally there’s an astral symbol (from the range of U+010000 to U+10FFFF). TL;DR Go forth and submit pull requests with piles of poo in them. It’s the only way to Unicode the Web Forward®.