Using `\renewcommand\footnoterule{}`in mdframed

Question

I am trying to remove a separator line for footnotes in mdframed environment. I tried using \renewcommand\footnoterule{} inside the mdframed environment, but this doesn't seem to work.

When I had to change the footnote symbol I had to use some temp values like this:

\renewcommand{\thempfootnote}{\color{white}{$\dagger$}} 

Are there any similar temp values for \footnoterule as well? It would be fine if I could either remove the black line or make it white...

---

MWE:

\documentclass[a4paper,10pt]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{color}
\usepackage{xcolor}

\usepackage[framemethod=TikZ]{mdframed}
\mdfdefinestyle{vprasanje}{%
    font=\normalsize,
    linecolor=red,
    outerlinewidth=0pt,
    roundcorner=2pt,
    innertopmargin=4pt,
    innerbottommargin=4pt,
    innerrightmargin=10pt,
    innerleftmargin=10pt,
    backgroundcolor=red,
    settings={\definecolor{linkcolor}{RGB}{255,255,255}}}

\usepackage{footmisc}
\def\footnotelayout{\color{white}}

\begin{document}
\begin{mdframed}[style=vprasanje]
\renewcommand\footnoterule{}
\renewcommand{\thempfootnote}{\color{white}{$\dagger$}}
\textcolor{white}{This is a footnote\footnote{You can see that line is still there and color is black...}}
\end{mdframed}
\end{document} 

rendered:

Answer 1

A quick glance at mdframed.sty shows (l. 745ff) that the package uses the internal macro \mdf@footnoterule instead of the "standard" \footnoterule (which is rather sensible). This internal macro is defined by

\newrobustcmd*\mdf@footnoterule{%
    \kern0\p@%
    \hrule \@width 1in \kern 2.6\p@}

(Don't ask me why \kern0\p@ instead of simply \kern\z@.) If you want to remove the line once and for all, one quick&dirty trick is simply to place

\makeatletter
\def\mdf@footnoterule{}
\makeatother

somewhere in the preamble. I think it should be safe, as this is used only by the macro actually typesetting the footnote.

EDIT: If you want to do something else, like change the color, you can adapt the code to your needs, like

\makeatletter
\renewrobustcmd*\mdf@footnoterule{%
    {\color{white}\kern0\p@%
    \hrule \@width 1in \kern 2.6\p@}}
\makeatother

Please notice 1) the use of \renewrobustcmd* and 2) the additional grouping around \color{white}. The latter is not strictly necessary in your MWE, as you are writing the text in white anyway, but it would matter otherwise.