Beamer sweeps direction for right to left language inside itemize

Question

I want to write a beamer document in Hebrew.

I noticed that it changes some environments from right-to-left to left-to-right. For example:

% !TEX TS-program = xelatex
% !TEX encoding = UTF-8

\documentclass[]{beamer}

\usepackage{polyglossia}
\setdefaultlanguage{hebrew}
\setotherlanguage{english}
\newfontfamily\englishfontsf{Latin Modern Roman}[Script=Latin,Language=English]
\newfontfamily\englishfont{Latin Modern Roman}[Script=Latin,Language=English]
\newfontfamily\hebrewfont{Arial}[Script=Hebrew]
\newfontfamily\hebrewfontsf{Arial}[Script=Hebrew]
\newfontfamily\HelveticaH{Open Sans Hebrew}[Script=Hebrew]
\begin{document}

\begin{frame}{כותרת השקופית}
ישנן שתי אפשרויות:

\begin{RTL}
\begin{itemize}
\item אפשרות מספר אחת
\item אפשרות מספר שתיים
\end{itemize}
\end{RTL}
\end{frame}
\end{document}

I even added manually the bidi package environment RTL, and the text is still typed in the other direction.

Why is that? Is there a way to solve it?

This question describes just the same situation, but it is way back from 2011, I want to believe that some work on this topic has done by the developers.

The second answer there gives a solution with LuaLaTeX, which I don't know how to use.

Answer 1

When i compile your code i don't get this error. Note that in the last update of the bidi package (version 39.5), some problems regarding RTL documents with beamer has been fixed.

Also, polyglossia loads bidi with the RTLdocument option when using Hebrew, so you don't really need to load it nor to start RTL environment by yourself.

Updating to the latest version might solve your problem. For more information about the matter, see the talk Vafa Khalighi gave in TuG 2022.