docs: private static boolean isValidCharacter(int ch) {
  		return
  			(ch >= 0x20 && ch <= 0xD7FF) // Most common condition first
  			|| ch == 0x9
  			|| ch == 0xA
  			|| ch == 0xD
  			|| (ch >= 0xE000 && ch <= 0xFFFD)
  			|| (ch >= 0x10000 && ch <= 0x10FFFF)
  		;
  	}