Format chapter title and use package `babel`

Question

I want to make the chapter number and title to be in the same line as this question. However, when I want to apply the answer, it does not work with the package babel with the option 'magyar'.

\documentclass[a4paper,12pt]{report}
% \usepackage[magyar]{babel}  % Does not work
\usepackage[english]{babel}   % Works
\usepackage{titlesec}
  \titleformat{\chapter}[hang]{\normalfont\huge\bfseries}{\chaptertitlename\ \thechapter:}{1em}{}
\usepackage{lipsum}
\begin{document}
\chapter{Introduction}
\lipsum[1]
\end{document}

Does anybody have an idea how to use \titleformat and babel together?

EDIT

According to @esdd answer the key is to use

\def\magyarOptions{chapterhead=unchanged}

before

\usepackage[magyar]{babel}

In this case, I had to reformat chapter title manually (to be 'magyar'):

\titleformat{\chapter}[hang]{\normalfont\huge\bfseries}{\arabic{chapter}. Fejezet:}{1ex}{}

Answer 1

You have to use \def\magyarOptions{chapterhead=unchanged} before loading package babel with option magyar.

\def\magyarOptions{chapterhead=unchanged}
\usepackage[magyar]{babel}

Example:

\documentclass[a4paper,12pt]{report}
\usepackage[T1]{fontenc}
\def\magyarOptions{chapterhead=unchanged}
\usepackage[magyar]{babel}
\usepackage{titlesec}
\titleformat{\chapter}[hang]{\normalfont\huge\bfseries}{\chaptertitlename\ \thechapter:}{1em}{}
\renewcommand*{\chaptertitlename}{\expandafter\MakeUppercase\chaptername}
\usepackage{xpatch}
\xapptocmd{\appendix}
  {\gdef\chaptertitlename{\expandafter\MakeUppercase\appendixname}}
  {}{\undefined}
\usepackage{lipsum}
\begin{document}
\tableofcontents
\chapter{Introduction}
\lipsum[1]
\appendix
\chapter{Appendix chapter}
\end{document}