@namespace url(http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul);

.tab-close-button, 
.tabs-closebutton, 
#find-closebutton {
  list-style-image: url("data:image/png;base64,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") !important;
  -moz-image-region: rect(0, 16px, 16px, 0) !important;
}

tab[selected="true"] .tab-close-button, 
.tabs-closebutton, 
tab:hover .tab-close-button, 
#find-closebutton {
  -moz-image-region: rect(16px, 16px, 32px, 0) !important;
}

tab .tab-close-button:hover, 
.tabs-closebutton:hover, 
#find-closebutton:hover {
  -moz-image-region: rect(32px, 16px, 48px, 0) !important;
}