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

.bookmark-item[label="about:config"],
#main-window[stylish-url="about:config"] #page-proxy-favicon,
.tabbrowser-tab[label="about:config"] .tab-icon-image {
  list-style-image: url("data:image/png;base64,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") !important;
}