improve explanation

base/doc/tlc3.err

@@ -1,4 +1,4 @@
-\newcommand\erratafiledate{2023/11/29}        % needs / and not -
+\newcommand\erratafiledate{2024/01/07}        % needs / and not -
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 % To produce a printed version of this errata file run this file through
@@ -1320,6 +1320,10 @@ is created only if the entry \u{contains} a shorttitle \u{field} and the title a
 is created only if the entry \u{has been referenced (prior to typesetting}\\
 \u{the bibliography), contains} a shorttitle \u{field,} and the title and shorttitle fields differ.
 
+\erroronpage{II-535}{footnote}{FMi}{2024/01/07}{}
+Extend the explanation:\\
+\u{you can} use \cs{mancite} \u{in front of any citation command} to avoid this.
+
 
 \erroronpage{II-560}{exa 16-7-31}{FMi}{2023/08/31}{s}
 Jane Doe.\ \textit{A\u{n} second book.}\ 2020.\> Jane Doe.\ \textit{A second book.}\ 2020.