Menü Chronik → "Synchronisierte Tabs" ohne Icon?!

menu[label="Kürzlich geschlossene Tabs"] {
    -moz-appearance: none!important;
    padding-right: 10px !important;
    background: url("xxxxxxxxxxxxxxxxxxxxxxxxxxxxx")no-repeat !important;
    background-position: 5px 2px!important;
}

menu[label="Kürzlich geschlossene Tabs"] [_moz-menuactive="true"]:hover { 
   -moz-appearance: none !important;
   background: url("xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx")no-repeat !important;
   background-position: 5px 2px !important;

}

#sync-tabs-menuitem{
-moz-appearance:none!important;
background: url("data:image/png;base64,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") no-repeat !important;
min-height: 24px!important;
padding-left:4px!important;
background-position:6px 5px!important;
}


#sync-tabs-menuitem:hover{
-moz-appearance:none!important;
margin-right: -1px !important;
background: #ecf0f6 url("data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAACXBIWXMAAA7DAAAOwwHHb6hkAAADcElEQVR4nHVTXWxTZRh+zzntOafn9Gdt3enoz8po2dauMLYat6iom5OpCwMGmswrLjRecAGBkDkTkCtCiDeQaGKCF7vQoBL0gpARJyFTxCDQwqA/6Nba/bU9Xdedru1pe3441Y2MGJ7kTb683/c835PvfT4E1jB66E2zQ2/4WG8wD+KUzmgwvsCwqYWSUC4VVSKXZsz6B6HH8c+OnPslBRuArS8yCzGqu9075vG2tkp8zhwLXieTM0HdcipmSubKlv1793Q1O5kjO1u08nfXo5P/Ezh/bOh0y9bNfdmFx8AmQiBUy4ChKFTxhspAfy9eb9ICRWCow2rqfcOjt34zEb3yVODCSM9Aq8t+vlLioLiSVjoIEFojqEmtfPt+5F5yOkgE7tymljJpqDfqwLmpzv+iiwpfmow/QmsCjYzxKzUiAggFIEkCArH83G+h9JiAGVJ3Zrh9uNpkUxH4udzyMvx6609IZ5Zg21b7F7WbsAuf9HXsaLYdl8QKIDLA71MJ9tufA+2hxeSP2z3t5MXxwJUbIVacCC6N7+5u7K7T0e4iXwUrU6exm/AfVEaafI8kcUVMBgRB4G5k/uzfSWBrzkY+v3hq44trCOKMXke/TRI4rBYqyA6P/SBKooJP2QCNYp3AcQhPZ6/Cc/Aono3ptBTUSo0TgKtU9agoVUVRFoE2bQKDmYF3X201P0+gKsrv6LQ0/FcUZLjSFJpcKl+ORKJA1VlBZ2uHXT0vndxIOjzUNliblt8P6ja3daRGpCgSaJqSI3H2Kpb/IxHydpo/RRAJtTZ3gaO5Y8vwK0z+y+9v3lKI6Ae97gkCFfS9Ps/Z9/v9XprSQKEkQI7jY/tGL5/E4gBSf5ezMfzwfudKJgFN23ZCQ9uu/pHhzuEOO/gseqxn4HXfa2+97LNqaQ1kuRJUBFEOhGc/unQjGkbWE/n10e7p2bk5Z21Em5tcYHe6gZ2bWTVoMK3DYYEtThtwRQHiC1lYzhXGDpz46SD8G7k1WCxAjw75g8nFRffKagkaLPW8BhXIRpsVXC4nJNJFKPIVKFeF8Idnrm1XKMIzf6FQAPnuP8I9iqI5bxNjL/CSSlKRMsej0oNpVszl+TxfFVO5QuVmdDExns9D9RkHa1AxDOOUZdmGYeBCAXHUzoiC9JcS9HklaPMsy8aUnrhOeALXrFu6bGkawwAAAABJRU5ErkJggg==") no-repeat !important;
border-width: thin !important;
border-radius: 4px !important;
border-color: #aecff7 !important;
border-style: solid !important;
min-height: 24px!important;
padding-left:3px!important;
background-position:5px 4px!important;}