Un esempio di codice da mettere in userChrome.css potrebbe essere questo:
treechildren::-moz-tree-image(flaggedCol, flagged) {
list-style-image: url("data:image/png;base64,iiVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAACXBIWXMAAAsTAAALEwEAmpwY
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") !important;
}
ATTENZIONE: tutto il codice da list-style-image fino a !important deve stare su un'unica riga!!!
La sintassi in via generale è questa:
treechildren::-moz-tree-image(flaggedCol, flagged) {
list-style-image: url("data:image/png;base64,<codice dell'immagine PNG codificata in base64>") !important;
}