在 captionsetup 中使用宽度时，longtable 会出现不需要的标题缩进

Question

如果我width=0.9\linewidth在 中使用，我会得到一个缩进的标题captionsetup。然后longtable标题会居中或缩进，并且没有办法让它与表格左对齐。但是，width在其他表格上工作正常。我使用它是因为我的文档中的一些标题很长，但我不想让它们一直延伸到文档的右边距。我曾尝试margin在 中使用captionsetup，但这会导致同样的问题。我也尝试在 captionsetup 中使用负缩进设置，但这只会影响标题的第二行，而不会影响表格编号。

以下是屏幕截图和 MWE：

\documentclass[12pt, a4paper]{memoir}
\usepackage{longtable}
\usepackage{csquotes}
\usepackage{tabularx}
\usepackage{multirow}
\usepackage{threeparttable} % for table notes
\usepackage{threeparttablex} % for longtable notes
\usepackage{caption}
\usepackage{siunitx} % align numbers by decimal point
\usepackage{lipsum}

%setup page
\settypeblocksize{237mm}{150mm}{*} % size of text block on page
\setulmargins{3.5cm}{*}{*} % sets start of text on page after ruled header
\setheadfoot{\onelineskip}{2\onelineskip}
\setheaderspaces{2cm}{*}{*} % start of rule header line on page
\setlrmarginsandblock{3.5cm}{2.5cm}{*} % left and right margins
\checkandfixthelayout

\sisetup{detect-family, add-integer-zero = false, group-digits = false}%

%adding width indents/centers longtable caption
\captionsetup[table]{textfont=it, justification=raggedright, singlelinecheck=off, format=plain, labelsep=newline, skip=5pt, width=0.9\linewidth}

%excluding width works
%\captionsetup[longtable]{justification=raggedright, labelsep=newline, singlelinecheck=off, textfont=it, skip=5pt, format=plain}

\begin{document}

%normal table
\begin{table}[!htb]
\begin{threeparttable}
\caption{Evaluation of some contexts based on some coordinates}
\label{some_tabel1}
\begin{tabularx}{\textwidth}{%
    X
    r
    p{1mm}
    p{20mm}
    S[table-format=2.0, table-column-width=12mm]
    S[table-format=2.0, table-column-width=12mm]
    S[table-format=2.0, table-column-width=12mm]
    S[table-format=2.0, table-column-width=12mm]
    }
\toprule
\multirow{2}[2]{*}{Sample context}
& \multirow{2}[2]{*}{\textit{N}}
&
& \multirow{2}[2]{1.8cm}{Proposed construct}
& \multicolumn{2}{c}{Some location}
& \multicolumn{2}{c}{Another location} \\
\cmidrule(r){5-6}
\cmidrule(l){7-8}
& & & & \multicolumn{1}{c}{\textit{n}}
& \multicolumn{1}{c}{\%}
& \multicolumn{1}{c}{\textit{n}}
& \multicolumn{1}{c}{\%} \\
\midrule
Item 1   &  $54$   && Low     &  23 &  43  & 31  &  57  \\
Item 2   &  $73$   && High    &  60 &  82  & 13  &  18  \\
Item 3   &  $80$   && High    &  72 &  90  &  8  &  10  \\
Item 4   &  $83$   && Medium  &  72 &  87  & 11  &  13  \\
Item 5   & $159$  && Rare    & 148 &  93  & 11  &  7   \\
\bottomrule
\end{tabularx}
\begin{tablenotes}[para,flushleft]
\small{\textit{Note}. Some further notes here.}
\end{tablenotes}
\end{threeparttable}
\end{table}

%longtable
\begin{ThreePartTable}
\begin{TableNotes}[para,flushleft]
\small{\textit{Note}. Some note text here.}
\end{TableNotes}

\setlength{\extrarowheight}{2mm} %add row padding before midrule
\begin{longtable}[!htb]{
        >{\raggedright}p{0.5cm}
        >{\raggedright}p{3.1cm} 
        >{\raggedright}p{8.5cm} 
        p{1.5cm}
    }
\caption[]{Severity of identified problems and proposed changes}
\label{some_lable2}\\
\toprule
\\ [-1.8\normalbaselineskip]
\multicolumn{2}{l}{Change} & Justification & Severity\\ %the first header
\midrule
\endfirsthead
\caption{Severity of identified problems and proposed changes (cont.)}\\
\toprule
\\ [-1.8\normalbaselineskip]
\multicolumn{2}{l}{Change} & Justification & Severity\\ %the following header(s)
\midrule
\endhead
\midrule
\\[-1.8\normalbaselineskip]
\multicolumn{4}{r}{\textit{continued}}
\endfoot
\\[-1\normalbaselineskip]
\bottomrule
\insertTableNotes
\endlastfoot
1. & Bullet point 1 and some extra sample text & \lipsum[1] & High \\
2. & Bullet point 2 & \lipsum[2] & Medium\\
3. & Bullet point 3 & \lipsum[3] & Low\\
\end{longtable}
\end{ThreePartTable}

\end{document}