lanx:~$ mkdir ~/.mozilla/firefox/vkuuxfit.default/chrome
lanx:~$ cd ~/.mozilla/firefox/vkuuxfit.default/chrome
lanx:~/.mozilla/firefox/vkuuxfit.default/chrome$ cat >userContent.css
@-moz-document  domain(board.perl-community.de){
.signature  {
 color: #ccc;
 border-top:1px solid #ccc;
 padding-top:0.5em;
 margin-top:0.5em;
 font-size:0.8em;
}
.signature a:link {color:#c67;}

.signature hr{display:none;}
}