Versuche es einfach mal nur mit:
CSS
		
					
				/* UserStyles Loader Button */
#usercssloader-menu-item {
	background-image: url("../icons/CSS.webp");
	background-position: center;
	background-repeat: no-repeat;
	background-size: 15px;
	margin-top: 1px !important;
}
#usercssloader-menu-item:hover {
	background-color: var(--toolbarbutton-hover-background);
}
#usercssloader-menu-item #usercssloader-menu > .menu-text[value="CSS"] {
	opacity: 0;
} 
		
		
	 
															
		










 
     
     
     
    


 
								
 
								 
     
    
 
    