Base64 encoding applied to different unicode texts always yields different base64 texts ... true or false?

[Peter Saint-Andre via Unicode]

On 10/14/18 3:59 PM, Philippe Verdy via Unicode wrote:
> 
> 
> Le dim. 14 oct. 2018 à 21:21, Doug Ewell via Unicode
> <unicode at unicode.org <mailto:unicode at unicode.org>> a écrit :
> 
>     Steffen Nurpmeso wrote:
> 
>     > Base64 is defined in RFC 2045 (Multipurpose Internet Mail Extensions
>     > (MIME) Part One: Format of Internet Message Bodies).
> 
>     Base64 is defined in RFC 4648, "The Base16, Base32, and Base64 Data
>     Encodings." RFC 2045 defines a particular implementation of base64,
>     specific to transporting Internet mail in a 7-bit environment.
> 
> 
> Wrong, this is "specific" to transporting Internet mail in any 7 bit or
> 8 bit environment (today almost all mail agents are operating in 8 bit),
> and then it is referenced directly by HTTP (and its HTTPS variant).
> 
> So this is no so "specific". MIME is extremely popular, RFC 4648 is
> extremely exotic (and RFC 4648 is wrong when saying that IMAP is very
> specific as it is now a very popular protocol, widely used as well).
> MIME is so frequently used, that almost all people refer to it when they
> look for Base64, or do not explicitly state that another definition
> (found in an exotic RFC) is explicitly used.

RFC 4648 is used in many, many Internet protocols. It's definitely not
"extremely exotic".

Peter