RFC 7991, "The "xml2rfc" Version 3 Vocabulary", December 2016

Errata ID: 4904
Status: Held for Document Update
Type: Editorial
Publication Format(s) : TEXT
Reported By: Julian Reschke
Date Reported: 2017-01-15
Held for Document Update by: Robert Sparks
Date Held: 2018-02-09

Section 2.25.2 says:

   Deprecated.  If the goal is to provide a single URI for a reference,
   use the "target" attribute in <reference> instead.

Notes:

This text doesn't make any sense, as the purpose for "alt" is something entirely different. The reason why it really was deprecated will have to be included here.

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