为什么“提升”的n定理证明环境有时无法添加QED符号？

Question

阅读：

带有 [amsthm] 选项的 ntheorem 忽略了定理环境的样式

我采用了建议的证明环境，ntheorem没有amsmath选项。我还确保将thmmarks选项添加到ntheorem，以启用定理结束/证明结束标记。但是 - 如果我写这个文档：

\documentclass{article}

\makeatletter

\usepackage[thmmarks]{ntheorem}
\usepackage{amssymb} % for \blacksquare
\usepackage{mathtools}

 \newcommand{\proofname}{Proof}
 \newcounter{proof}\newcounter{currproofctr}\newcounter{endproofctr}%
 \newenvironment{proof}[1][\proofname]{
  \th@nonumberplain
  \def\theorem@headerfont{\itshape}%
  \normalfont
  \@thm{proof}{proof}{{#1}.}}%
   {\@endtheorem} % and this ends the definition of the proof environment

\newcommand\proofSymbol{\ensuremath{\blacksquare}}
\qedsymbol{\ensuremath{\blacksquare}}

\makeatother

\begin{document}

\begin{proof}
    The quick brown fox jumped over the lazy dog 1.
\end{proof}

\begin{proof}
    The quick brown fox jumped over the lazy dog 2.
    \begin{align*}
    42        
    \end{align*}
\end{proof}

and some text afterwards.

\end{document}

我得到第一个校样上有黑色方块，但第二个校样上没有。这是为什么？

Answer 1

看起来常规界面按预期工作（编译两次后），包括修改后的格式：

\documentclass{article}

\usepackage{amsmath}
\usepackage[amsmath,thmmarks]{ntheorem}
\usepackage{amssymb} % for \blacksquare
\usepackage{mathtools}

\theoremstyle{plain}
\theorembodyfont{\normalfont}
\theoremheaderfont{\normalfont\itshape}
\theoremseparator{.}
\theoremsymbol{\ensuremath{\blacksquare}}
\newtheorem{proof}{Proof}
\begin{document}

\begin{proof}
    The quick brown fox jumped over the lazy dog 1.
\end{proof}

\begin{proof}
    The quick brown fox jumped over the lazy dog 2.
    \begin{align*}
    42        
    \end{align*}
\end{proof}

and some text afterwards.

\end{document}