doc: added sentence about limitations of xelatex

CHANGELOG.md

@@ -8,6 +8,10 @@ a major and minor version only.
 
 ## [Unreleased]
 
+### Added
+
+- doc: added sentence about limitations of xelatex
+
 ### Changed
 
 - unified usage of `(sub)section in head/foot` template in headlines

doc/beamerug-introduction.tex

@@ -23,7 +23,8 @@ \subsection{Main Features}
 The list of features supported by \beamer\ is quite long (unfortunately, so is presumably the list of bugs supported by \beamer). The most important features, in our opinion, are:
 \begin{itemize}
 \item
-  You can use \beamer\ with |pdflatex|, |latex|+|dvips|, |lualatex| and |xelatex|. |latex|+|dvipdfm| isn't supported (but we accept patches!).
+  You can use \beamer\ with |pdflatex|, |latex|+|dvips| and |lualatex|. \beamer\ documents can also be compiled with |xelatex|, however the results might show some elements incorrectly and there are other limitations of the engine, which are described in more detail in e.g.\ \url{https://www.texdev.net/2024/11/05/engine-news-from-the-latex-project}.
+  |latex|+|dvipdfm| isn't supported (but we accept patches!).
 \item
   The standard commands of \LaTeX\ still work. A |\tableofcontents| will still create a table of contents, |\section| is still used to create structure, and |itemize| still creates a list.
 \item