How to break the email-address in behind the @-symbol (scrlttr2)

Question

I like to write a letter in latex, it all works fine so far, i just find that the sender information on the top rightis kind of "ugly". This results from the long email-address pushing the entire block to the left:

Firstname Lastname
Street 001
9999 Cityname
Telefon: +43 9999 999 2
Email: first.lastname@alumni.university.edu

Is it possible to force a line break after the @-symbol aligning the adress with the rest of the information so it looks like below?

Firstname Lastname
Street 001
9999 Cityname
Telefon: +43 9999 999 2
Email: first.lastname@
       alumni.university.edu

Here is the MWE:

\documentclass[version=last]{scrlttr2}
\usepackage[ngerman]{babel}
\usepackage{graphics}
\LoadLetterOption{DIN}
\usepackage{hyperref}
\KOMAoptions{
    paper=a4,
    pagenumber=botcenter,
    fromemail,
    backaddress,
    foldmarks,
    enlargefirstpage,
    foldmarks=true,
    fromrule=afteraddress,
    fromphone,fromemail,
}
\hypersetup{
    colorlinks=false,
    hidelinks=true,
}
\makeatletter\setkomavar{firsthead}{%
    \hspace*{\fill}\footnotesize
    \begin{tabular}{l@{}}
        \usekomavar{fromname}\\
        \usekomavar{fromaddress}
        \if@phone\\
        \usekomavar*{fromphone}\usekomavar{fromphone}\fi
        \if@fax\\
        \usekomavar*{fromfax}\usekomavar{fromfax}\fi
        \if@email\\
        \usekomavar*{fromemail}\usekomavar{fromemail}\fi
        \if@www\\
        \usekomavar*{fromurl}\usekomavar{fromurl}\fi
    \end{tabular}%
}\makeatother
\setkomavar{fromname}{Firstname Lastname}
\setkomavar{fromaddress}{Street 001\\9999 Cityname}
\setkomavar{fromphone}{+43\,9999\,999\,2}
\setkomavar{fromemail}{\href{mailto:first.lastname@alumni.university.edu}{first.lastname@alumni.university.edu}}
\begin{document}
\begin{letter}{%
Company\\
Mainstreet 001\\
1111 Cityname
}
\setkomavar{subject}{Subject}

\opening{Dear Mr. X,}
This is some text.
\closing{Cheers}
\end{letter}
\end{document}

Thank you in advance :)

Answer 1

Try this:

\documentclass[version=last]{scrlttr2}
\usepackage[ngerman]{babel}
\usepackage{graphics}
\LoadLetterOption{DIN}
%\LoadLetterOption{Absender}
\usepackage{hyperref}
\KOMAoptions{
    paper=a4,
    pagenumber=botcenter,
    fromemail,
    backaddress,
    foldmarks,
    enlargefirstpage,
    foldmarks=true,
    fromrule=afteraddress,
    fromphone,fromemail,
}
\hypersetup{
    colorlinks=false,
    hidelinks=true,
}
\newsavebox{\mybox}
\newcommand{\myBrokenEmail}[2]{\savebox\mybox{\hbox{E-Mail:\space}}#1\\\hspace*{\wd\mybox}#2}

\setkomavar{fromname}{Firstname Lastname}
\setkomavar{fromaddress}{Street 001\\9999 Cityname}
\setkomavar{fromphone}{+43\,9999\,999\,2}
\setkomavar{fromemail}{\href{mailto:first.lastname@alumni.university.edu}{\myBrokenEmail{first.lastname@}{alumni.university.edu}}}
\begin{document}
\begin{letter}{%
Company\\
Mainstreet 001\\
1111 Cityname
}
\setkomavar{subject}{Subject}

\opening{Dear Mr. X,}
This is some text.
\closing{Cheers}
\end{letter}
\end{document}

Output:

EDIT:

A second way if really a tabular is used:

\documentclass[version=last]{scrlttr2}
\usepackage[ngerman]{babel}
\usepackage{graphics}
\LoadLetterOption{DIN}
%\LoadLetterOption{Absender}
\usepackage{hyperref}
\KOMAoptions{
    paper=a4,
    pagenumber=botcenter,
    fromemail,
    backaddress,
    foldmarks,
    enlargefirstpage,
    foldmarks=true,
    fromrule=afteraddress,
    fromphone,fromemail,
}
\hypersetup{
    colorlinks=false,
    hidelinks=true,
}
% Here is the command to be used:
\newcommand{\myBrokenEmail}[2]{\begin{tabular}[t]{@{}l@{}}#1\\#2\end{tabular}\vspace{8pt}}

\setkomavar{fromname}{Firstname Lastname}
\setkomavar{fromaddress}{Street 001\\9999 Cityname}
\setkomavar{fromphone}{+43\,9999\,999\,2}
\setkomavar{fromemail}{\href{mailto:first.lastname@alumni.university.edu}{\myBrokenEmail{first.lastname@}{alumni.university.edu}}}
\begin{document}
\begin{letter}{%
Company\\
Mainstreet 001\\
1111 Cityname
}
\setkomavar{subject}{Subject}

\opening{Dear Mr. X,}
This is some text.
\closing{Cheers}
\end{letter}
\end{document}

Answer 2

With a slightly modification of the answer of @kolegyr you can still use \usekomavar{fromemail} to get the email without breaks:

\documentclass[version=last]{scrlttr2}
\usepackage[ngerman]{babel}
\usepackage{graphics}
%\LoadLetterOption{DIN}% default
\usepackage{hyperref}
\KOMAoptions{
    %paper=a4,% default
    pagenumber=botcenter,
    %fromemail,% used twice
    %backaddress,% default
    %foldmarks,% default
    enlargefirstpage,
    %foldmarks=true,% default (and used twice)
    %fromrule=afteraddress,
    fromphone,fromemail
}
\hypersetup{
    %colorlinks=false,% not needed if hidelinks is used
    hidelinks%=true,% no key-value-option
}

\makeatletter\setkomavar{firsthead}{%
    \hspace*{\fill}\footnotesize
    \begin{tabular}{l@{}}
        \usekomavar{fromname}\\
        \usekomavar{fromaddress}
        \if@phone\\
        \usekomavar*{fromphone}\usekomavar{fromphone}\fi
        \if@fax\\
        \usekomavar*{fromfax}\usekomavar{fromfax}\fi
        \if@email\\
        \usekomavar*{fromemail}\usekomavar[\let\EmailFormat\EmailInHeader]{fromemail}\fi
        \if@www\\
        \usekomavar*{fromurl}\usekomavar{fromurl}\fi
    \end{tabular}%
}\makeatother
\setkomavar{fromname}{Firstname Lastname}
\setkomavar{fromaddress}{Street 001\\9999 Cityname}
\setkomavar{fromphone}{+43\,9999\,999\,2}
\setkomavar{fromemail}{\href{mailto:first.lastname@alumni.university.edu}{\EmailFormat{first.lastname@}{alumni.university.edu}}}

\newcommand\EmailFormat[2]{#1#2}
\newcommand\EmailInHeader[2]{\begin{tabular}[t]{@{}l@{}}#1\\#2\end{tabular}}

\begin{document}
\begin{letter}{%
Company\\
Mainstreet 001\\
1111 Cityname
}
\setkomavar{subject}{Subject}

\opening{Dear Mr. X,}
This is some text.

The email in a single line:  \usekomavar{fromemail}
\closing{Cheers}
\end{letter}
\end{document}

Result: