For customizing the appearance of Firefox browser

userChrome.css

/* Smaller search button paddings */
.search-one-offs {
    padding-top: 6px !important;
    padding-bottom: 7px !important;
}

/* Disable Megabar Animation */
#urlbar[breakout][breakout-extend][breakout-extend-animate] > #urlbar-background {
    animation-name: none !important;
    animation: none !important;
}

/* --- Move the type icons to the left of the favicon. --- */
.urlbarView.megabar .urlbarView-favicon {
    margin-left: 20px !important;
}

.urlbarView.megabar .urlbarView-type-icon {
    position: relative !important;
    left: -54px !important;
    top: -4px !important;
    margin-right: -24px !important;
    height: 16px !important;
    width: 16px !important;
    filter: contrast(90%) brightness(110%);
}