\newunicodechar 出现 U+21B3 UTF8 字符故障

Question

下列

% file testbismon.tex
%% see https://github.com/bstarynk/bismon/ for more about Bismon
\documentclass[11pt,a4paper,svgnames]{article}
\usepackage[T1]{fontenc}
\usepackage[utf8x]{inputenc}
\usepackage{alltt}
% https://tex.stackexchange.com/a/342804/42406
%\usepackage{textcomp}
\usepackage{moreverb}
\usepackage{fancyvrb}
\usepackage{fancyhdr}
\usepackage{fancybox}
\usepackage{epsfig}
\usepackage{makeidx}
\usepackage{float}
\usepackage{xcolor}
\usepackage{hyperref}
\usepackage{moreverb}
\usepackage{multirow}
\usepackage{boxedminipage}
\usepackage[square]{natbib}
\usepackage{charter}
%\usepackage{inconsolata}
\usepackage{listings}
\usepackage{relsize}
\usepackage{verbatimbox}
\usepackage{filecontents}
\usepackage{catchfile}
\usepackage{lastpage}
\usepackage{stmaryrd}
\usepackage{ucs}
\usepackage{stix}
\usepackage{newunicodechar}
% bigfoot enables \verb in footnotes
\usepackage{bigfoot}
\usepackage[a4paper, margin=2cm]{geometry}

\newcommand{\bmemail}[1]{{\href{mailto:#1}{\texttt{\textbf{#1}}}}}
\newcommand{\bmurl}[1]{{\href{#1}{\texttt{\textbf{#1}}}}}


% see also http://www.sascha-frank.com/Arrow/latex-arrows.html and
% https://ctan.math.illinois.edu/macros/latex/contrib/newunicodechar/newunicodechar.pdf
% and https://tex.stackexchange.com/a/238135/42406
\newunicodechar{↳}{\rotatebox[origin=c]{180}{$\Lsh$}}

\begin{document}
\section{the test}
\begin{alltt}
the U+21B3 character is {\large ↳} \textit{DOWNWARDS ARROW WITH TIP RIGHTWARDS}
\end{alltt}
\end{document}

在我的 Debian/Sid 机器上无法工作，因为pdflatex testbismon.tex出现以下错误：

...
(/usr/share/texlive/texmf-dist/tex/latex/ucs/data/uni-33.def)
(/usr/share/texlive/texmf-dist/tex/latex/ucs/data/uninames.dat)
(/usr/share/texlive/texmf-dist/tex/latex/ucs/data/uni-33.def)

! Package ucs Error: Unknown Unicode character 8627 = U+21B3,
(ucs)                possibly declared in uni-33.def.
(ucs)                Type H to see if it is available with options.

See the ucs package documentation for explanation.
Type  H <return>  for immediate help.
 ...                                              

l.50 the U+21B3 character is {\large ↳
                                        } \textit{DOWNWARDS ARROW WITH TIP R...

? 

为什么会出现这个错误？如何解决？

我的上述 LaTeX 代码灵感来自这答案。我正在使用：

 pdfTeX 3.14159265-2.6-1.40.20 (TeX Live 2019/Debian)
 kpathsea version 6.3.1

并使用 emacs 26 输入我的 LaTeX 文件。

Answer 1

您还可获得

Package newunicodechar Warning: This package only works if the document
(newunicodechar)                encoding is `utf8'.

删除\usepackage[utf8x]{inputenc}和\usepackage{ucs}。

无关但重要：hyperref应该是您长长的软件包列表中的最后一个。此外，使用charter和stix是矛盾的，删除前者。我不会stmaryrd和一起加载stix。和epsfig不能在较新的文档中使用：只需使用graphicx和其功能即可。