fix(manual): use render instead for the colormixin example

doc/generic/pgf/CHANGELOG.md

@@ -9,6 +9,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 ### Fixed
 
 - `sloped` should consider the current transformation #1058
+- Use `render instead` for the `colormixin` example #1134
 
 ### Changed
 

doc/generic/pgf/pgfmanual-en-xxcolor.tex

@@ -33,18 +33,41 @@ \section{Extended Color Support}
     |90!blue| will mix in 10\% of blue into everything, whereas |25!white| will
     make everything nearly white.
     %
-\begin{codeexample}[width=4cm,preamble={\usepackage{xxcolor}}]
+\begin{codeexample}[%
+  width=4cm,
+  preamble={\usepackage{xxcolor}},
+  % We use render instead with the exact same content here, because the normal
+  % codeexample is rendered in hmode with \catcode`\^^M=9 which ignores all line
+  % endings instead of converting them to spaces.  Using \catcode`\^^M=10 in
+  % contrast would correctly convert line endings to spaces, but that leads to
+  % spurious spaces because of how the example is absorbed token-by-token by the
+  % renderer.  Sigh...
+  render instead={%
+    \begin{minipage}{3.5cm}\raggedright
+    \color{red}Red text,
+    \begin{colormixin}{25!white}
+      washed-out red text,
+      \color{blue}washed-out blue text,
+      \begin{colormixin}{25!black}
+        dark washed-out blue text,
+        \color{green}dark washed-out green text,
+      \end{colormixin}%
+      back to washed-out blue text,
+    \end{colormixin}%
+    and back to red.
+    \end{minipage}%
+  }]
 \begin{minipage}{3.5cm}\raggedright
-\color{red}Red text,%
+\color{red}Red text,
 \begin{colormixin}{25!white}
   washed-out red text,
-  \color{blue} washed-out blue text,
+  \color{blue}washed-out blue text,
   \begin{colormixin}{25!black}
     dark washed-out blue text,
-    \color{green} dark washed-out green text,%
-  \end{colormixin}
-  back to washed-out blue text,%
-\end{colormixin}
+    \color{green}dark washed-out green text,
+  \end{colormixin}%
+  back to washed-out blue text,
+\end{colormixin}%
 and back to red.
 \end{minipage}%
 \end{codeexample}

doc/generic/pgf/pgfmanual-test.tex

@@ -17,6 +17,6 @@
 
 \begin{document}
 
-\include{pgfmanual-en-pgfkeys}
+\include{pgfmanual-en-xxcolor}
 
 \end{document}