makeatletter
newenvironment*{sidebar}[3][0.5textwidth]
{
    % less vertical margin around wrapfigures
    setlength{intextsep}{0pt}
    colorlet{savedcolor}{inline code}
    colorlet{inline code}{inline code inverted}
    renewcommand{dummy}{#1}
    wrapfigure{#2}{#1}
        renewcommand{@currentlabel}{#3}
        renewcommand{@currentlabelname}{#3}
        phantomsection
        rule{#1}{1pt}

        rule{#1}{18pt}

        vspace{-18pt}
        centerline{textcolor{white}{#3}}

        vspace{5pt}
        footnotesize
        leftskip=5pt
        rightskip=5pt
        setlength{parskip}{0.2cm}
        setlength{parindent}{0pt}
        % restore the inline code color for the body of the bar
        colorlet{inline code}{savedcolor}
}
{

        leftskip=0pt
        rightskip=0pt
        setlength{parindent}{0pt}
        rule{dummy}{1pt}
        rule[.19in]{dummy}{2.5pt}
    endwrapfigure
}
makeatother

% !TEX program = xelatex

documentclass{scrbook}

usepackage{wrapfig}
usepackage{graphicx}
usepackage{xcolor}
usepackage{tcolorbox}
usepackage{listings}
usepackage{blindtext}
usepackage{hyperref}

definecolor{inline code}{RGB}{194,61,53}
definecolor{inline code inverted}{RGB}{193,153,151}

newcommand*{code}{lstinline[basicstyle=fontsize{9}{11}ttfamilycolor{inline code},keywordstyle=color{inline code},stringstyle=color{inline code},keepspaces=true]}

newtcolorbox{cbar}[2][]{
    parbox=false, % normal paragraph spacing
    height from=2.5cm to 100cm,
    halign=justify,
    sharp corners,
    colframe=black,
    colback=black!15!white,
    fontupper=tiny,% font size for body of text
    title=scriptsize textsc{#2},
    #1
}

begin{document}

begin{cbar}[label=lab:testing]{Test Bar (some code{Code})}
    Here is a test bar with some code{Code}.

    blindtext
end{cbar}

Hello, code{code}. And here is a reference to ref{lab:testing}, which has name nameref{lab:testing}.

end{document}