How to prevent newtx from changing footnotemark style?

Question

I am using LuaTex with newtx package. However, using newtx changes the style of the \footnotemark command. However, I want the original style of \footnotemark in the superscript without the square brackets. How can I get back the default style?

MWE:

\documentclass[aspectratio=169]{beamer}
\usepackage{newtx}
\usepackage{fontspec}
\begin{document}
\begin{frame}{Test title}
  Test text.\footnotemark[1]
\end{frame}
\end{document}

MWE without newtx package:

MWE with newtx package:

Answer 1

EDIT: The issue should've been fixed with v1.73 2023-10-29

Something is very fishy. When Unicode engines are used (and no KOMA class), then newtxtext does

% newtxtext.sty l. 507
\renewcommand{\footnotemark}{\normalfont}

which is definitely a bug. Not sure what it should've been, but a workaround would be

\let\originalfootnotemark\footnotemark
\usepackage{newtx}
\let\footnotemark\originalfootnotemark

Answer 2

If you are anyway compiling with lualatex and the fontspec package, you could directly use a font of your choice:

% !TeX TS-program = lualatex
\documentclass[aspectratio=169]{beamer}
%\usepackage{newtx}
\usepackage{newtxmath}
\usepackage{fontspec}
\setsansfont{TeX Gyre Termes}
\begin{document}
\begin{frame}{Test title}
  Test text.\footnotemark[1]
\end{frame}
\end{document}