Clarify -push/-pop vs -font

cpdfmanual.tex

@@ -4407,6 +4407,8 @@ PDF maintains a stack of graphics state, which we can manipulate with \texttt{-p
 
 \noindent This is important because, in the absence of \texttt{-push} and \texttt{-pop} there would be no way to reverse the effect of a graphics matrix modification except to manually calculate its inverse and apply it.
 
+NB: When writing text (see below) the \texttt{-font} option is not subject to \texttt{-push} and \texttt{-pop}. Text is set the the font most recently chosen on the command line.
+
 \section{Re-use with XObjects}
   {\small\begin{framed}
    \vspace{1.5mm}
@@ -4599,6 +4601,8 @@ We can change the text rendering mode to show outline text or, in this example,
 \end{tabular}
 \bigskip
 
+NB: When writing text the \texttt{-font} option is not subject to \texttt{-push} and \texttt{-pop}. Text is set the the font most recently chosen on the command line.
+
 \section{The next page}
 
   {\small\begin{framed}