Make firefox pinned tabs wider

user.css

@namespace url(http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul);
/* https://gist.github.com/non7top/9617943d02aa51d3377d */
 
/* wider and better looking pinned tabs */
.tabbrowser-tab[pinned] {
width: 50px;
}

/* wider and better looking pinned tabs */
.tab-throbber[pinned],
.tab-icon-image[pinned] {
  -moz-margin-start: 11px !important;
  -moz-margin-end: 6px !important;
} 

/* highlight pinned tabs on change */
.tabbrowser-tab[pinned][titlechanged]:not([selected="true"]) {
   background: red !important;
}

/* show dropdown at searchbar */
searchbar .autocomplete-history-dropmarker {
-moz-binding: url("chrome://global/content/bindings/autocomplete.xml#history-dropmarker");
display: -moz-box;
}