I have code. In this code the url break in \printbibliography is not working. The url break in \url is working. Code:
\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage{filecontents}
\usepackage[backend=biber]{biblatex}
\begin{filecontents*}{references.bib}
@misc
{
mybibkey,
url = {http://de.wikipedia.org/wiki/Elementarladungasdlfkjasalsdkfjhalskdjdfhjalksdjdfhjalksjdfhj}
}
\end{filecontents*}
\addbibresource{references.bib}
\usepackage{hyperref}
\makeatletter
\g@addto@macro\UrlBreaks
{%
\do\a\do\b\do\c\do\d\do\e\do\f\do\g\do\h\do\i\do\j%
\do\k\do\l\do\m\do\n\do\o\do\p\do\q\do\r\do\s\do\t%
\do\u\do\v\do\w\do\x\do\y\do\z\do\&\do\1\do\2\do\3%
\do\4\do\5\do\6\do\7\do\8\do\9\do\0\do\/\do\.%
}
\g@addto@macro\UrlSpecials
{%
\do\/{\mbox{\UrlFont/}\hskip 0pt plus 2pt}%
}
\makeatother
%\usepackage{breakurl}
\begin{document}
See~\cite{mybibkey}.
\printbibliography
\noindent\url{http://de.wikipedia.org/wiki/Elementarladungasdlfkjasalsdkfjhalskdjdfhjalksdjdfhjalksjdfhj}
\end{document}
Output:

I get a warning from writeLaTeX if I uncomment \usepackage{breakurl}:
/usr/share/texlive/texmf-dist/tex/latex/breakurl/breakurl.sty:
Package breakurl Warning: You are using breakurl while processing via pdflatex.
How to solve? There are many google entries and stack exchange entries about this issue but nothing is working.

\setcounter{biburllcpenalty}{1}to allow breaks after lowercases. See the documentation for others.breakurlis sense- and useless with pdflatex. – Ulrike Fischer Oct 16 '14 at 07:45