userChrome.css

border-radius: 6px;

/* hide the Back button when there's nothing to go back to */
#back-button[disabled="true"] {
  display: none !important;
}
/* hide the Forward button when there's nothing to go forward to */
#forward-button[disabled="true"] {
display:none !important;
}

#forward-button{
padding-right:0px !important;
}
/*Change bookmark font*/
#PersonalToolbar .toolbarbutton-text {
font-size: 12.5px !important; }

/*Remove dropdown marker*/
.toolbarbutton-menu-dropmarker
{
   display: none !important;
}

/*Remove tabbar border*/
.tabbrowser-tabs{
border:none !important;
padding-top: 10px !important;
}

/*transparent url bar*/
#urlbar{
background-position: right !important;
-moz-appearance: none !important;
border: 0 !important;
margin: 0 !important;
padding-top: 5 !important;
height: 22px !important;
}


#urlbar-icons > #star-button
{
display:   none !important;
}

#urlbar-icons > #go-button
{
   display:   none !important;
}

#feed-button
{
display: none !important
}

.autocomplete-history-dropmarker { display: none !important;}