Extra space before labeled theorem body with thmbox or thmtools+thmbox

Question

Package thmbox seems to add an extra space at the beginning of the body of the labeled theorems. See example below. Package thmtools with the thmbox option does the same. Latex original, package amsthm and package ntheorem do not add the extra space. I can solve the problem that occurs with thmbox by placing a % just after the label. However, I do not want to do that because I should edit each already written theorem. Problem is solved by including \ignorespaces in option bodystyle of thmbox. However, then the body is indented. If bodystyle is defined using \noindent\ignorespaces then the body is not indented, but the extra space shows up again.

\documentclass{report}

% ----- no extra space

%\newtheorem{theorem}{Theorem}

%\usepackage{amsthm}
%\newtheorem{theorem}{Theorem}

%\usepackage{ntheorem}
%\newtheorem{theorem}{Theorem}

% ----- extra space

\usepackage{thmbox}
\newtheorem{theorem}{Theorem}

%\usepackage{thmtools}
%\declaretheorem[thmbox=M]{theorem}

\begin{document}

\begin{theorem}\label{L1}
With label.
\end{theorem}
\begin{theorem}
Without label.
\end{theorem}
\begin{theorem}     \label{L2}%
     With label, but solved, even having space characters here and there.
\end{theorem}

\end{document}

Answer 1

Put the \label at the end:

\begin{theorem}
With label.\label{L1}
\end{theorem}

It's a bug in thmbox way of doing its work.