# Remove thin border around mdframed title

I get a thin border around the title of a mdframed environment which has the color of the actual content area:

I want to get rid of this thin red line around the title.

MWE:

\documentclass{article}

\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}

\usepackage[usenames]{color}

% framemethod=TikZ is required to draw rounded corners
\usepackage[framemethod=TikZ]{mdframed}

\begin{document}

\mdfdefinestyle{eliasp}{%
roundcorner=3pt,
frametitlebackgroundcolor=yellow,
backgroundcolor=red,
hidealllines=true,
frametitle=This is the title,
}

\begin{mdframed}[style=eliasp]
This is some text
\end{mdframed}

\end{document}

-
That is an artifact that stems from the construction of the frame and is less-and-less visible at higher resolution. If you wish to remove it, you'll have to construct the header separately from the body and/or not have a generic macro that inserts say a 0pt line around the outer edge. This latter comment might be how mdframed actually constructs its frames in a general way. –  Werner Jun 19 at 23:10