Problem Description

I am a newbie. I use microtype package. I would like to set the minimum width of a space to a width of a regular space. However, with default settings, it is shrinked too much and I think it makes the text less readable.

Minimal Working Example

%%%%%  Preamble  %%%%%

documentclass[10pt]{book}

% usepackage[a4paper]{geometry}

usepackage[

    paperheight=7cm,

    paperwidth=21cm,

    top=1in,

    bottom=1in,

    right=1in,

    left=1in,

    portrait]{geometry}



usepackage[slovak]{babel}

usepackage{microtype}

usepackage{xcolor}



% Font family

usepackage[math-style=ISO, bold-style=ISO, partial=upright, nabla=upright]{unicode-math}

setmainfont{Libertinus Serif}



% Paragraph and line settings

setlength{parindent}{0em}           % Set paragraph indentation

setlength{parskip}{0.08in}          % Paragraph spacing

renewcommand{baselinestretch}{1.0}  % Line expandafterselectlanguageexpandafter{cvlang}



% Custom commands

newcommand{paragraphStyle}[1]{%

    par

    begingroup

        setlength{parindent}{0pt}%

        setlength{parskip}{0.16in}%

        renewcommand{baselinestretch}{1.0}%

        fontsize{20pt}{24pt}selectfont

        noindentcolor{black!100}%

        bfseriesignorespaces #1par

    endgroup

}



%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%



begin{document}

    pagestyle{empty}

    paragraphStyle{

        Pripomenieme si Pánovo zmŕtvychvstanie, budeme počúvať

    }

end{document}

Output

You can use the WordSpace option to adjust the space. The value is a scale factor (3 is too much and only used for the demo here). It is also possible to adjust the stretch and shrink value individually, see the documentation of fontspec.

documentclass[10pt]{book}



usepackage[slovak]{babel}

usepackage{microtype}

usepackage{xcolor}



% Font family

usepackage[math-style=ISO, bold-style=ISO, partial=upright, nabla=upright]{unicode-math}

setmainfont{Libertinus Serif}[WordSpace={3}]

begin{document}



        Pripomenieme si Pánovo zmŕtvychvstanie, budeme počúvať



end{document}

documentclass[10pt]{book}

% usepackage[a4paper]{geometry}

usepackage[

    paperheight=7cm,

    paperwidth=21cm,

    top=1in,

    bottom=1in,

    right=1in,

    left=1in,

    portrait]{geometry}



usepackage[slovak]{babel}

usepackage{microtype}

usepackage{xcolor}



% Font family

usepackage[math-style=ISO, bold-style=ISO, partial=upright, nabla=upright]{unicode-math}

setmainfont{Libertinus Serif}



% Paragraph and line settings

setlength{parindent}{0em}           % Set paragraph indentation

setlength{parskip}{0.08in}          % Paragraph spacing

renewcommand{baselinestretch}{1.0}  % Line expandafterselectlanguageexpandafter{cvlang}



% Custom commands

newcommand{paragraphStyle}[1]{%

    par

    begingroup

        setlength{parindent}{0pt}%

        setlength{parskip}{0.16in}%

        setlengthspaceskip{12pt plus 2pt minus 2pt }% word space

        setlengthxspaceskip{14pt plus 4pt minus 2pt }% end of sentence space

        renewcommand{baselinestretch}{1.0}%

        fontsize{20pt}{24pt}selectfont

        noindentcolor{black!100}%

        bfseriesignorespaces #1par

    endgroup

}



%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%



begin{document}

    pagestyle{empty}

    paragraphStyle{

        Pripomenieme si Pánovo zmŕtvychvstanie, budeme počúvať

    }

end{document}