Can a valid Unicode string contain FFFF? Is Java/CharacterIterator broken?...

Why are certain characters prohibited in the HTML5 spec?...

Is this Google Closure UTF-8 string valid?...

Which nonnegative integers aren't assigned a character in the UCS?...

Which unicode code can be used safely as reserved value?...

Strip invalid and noncharacters from utf8...

What's the purpose of the noncharacters U+FDD0 to U+FDEF?...