Notes:

1. Some browsers may not be able to display all Unicode characters; they may display blanks, boxes, or question marks for some characters. Installing more fonts may help.
2. Cutting and pasting does not work reliably in all browsers.
3. When cutting and pasting hex numbers from dump output on little-endian machines (eg x86), beware of byte order problems.
4. Hex numbers should not be prefixed with "0x", "U+", or anything else.
5. When entering a character in UTF-8 as multiple hex or octal bytes, the bytes should be separated by spaces.
6. "UTF-8 bytes as Latin-1 characters" is what you typically see when you display a UTF-8 file with a terminal or editor that only knows about 8-bit characters.
7. Spaces are ignored in the input of bytes as Latin-1 characters, to make it easier to cut-and-paste from dump output.