On the question How to stop the package \usepackage{parskip} disabling the paragraph indentation?, I learned how to restore the \parindent value zeroed by parskip:
\edef\restoreparindent{\parindent=\the\parindent\relax}
\usepackage{parskip}
\restoreparindent
Now I find out, that parskip is also zeroing something else I do not want to. Reading its documentation it explains:
In addition, the package adjusts the skips between list items.
How to extend the code above to also restore the list items spacing, after parskip zeros them?