• .css para a barra do Firefox reaparecer em tela cheia com o hover do mouse, dentro da pasta chrome no perfil do usuário (via git e Reddit)
    Código:

    /* Source file https://github.com/MrOtherGuy/firefox-csshacks/tree/master/chrome/autohide_toolbox.css made available under Mozilla Public License v. 2.0
    See the above repository for updates as well as full license text. */

    /* Hide the whole toolbar area unless urlbar is focused or cursor is over the toolbar
    * Dimensions on non-Win10 OS probably needs to be adjusted.
    */

    :root{
    --uc-autohide-toolbox-delay: 200ms; /* Wait 0.1s before hiding toolbars */
    --uc-toolbox-rotation: 82deg; /* This may need to be lower on mac - like 75 or so */
    }

    :root[sizemode="maximized"]{
    --uc-toolbox-rotation: 88.5deg;
    }

    @media (-moz-platform: windows){
    :root:not([lwtheme]) #navigator-toolbox{ background-color: -moz-dialog !important; }
    }

    :root[sizemode="fullscreen"],
    :root[sizemode="fullscreen"] #navigator-toolbox{ margin-top: 0 !important; }

    #navigator-toolbox{
    --browser-area-z-index-toolbox: 3;
    position: fixed !important;
    background-color: var(--lwt-accent-color,black) !important;
    transition: transform 82ms linear, opacity 82ms linear !important;
    transition-delay: var(--uc-autohide-toolbox-delay) !important;
    transform-origin: top;
    transform: rotateX(var(--uc-toolbox-rotation));
    opacity: 0;
    line-height: 0;
    z-index: 1;
    pointer-events: none;
    width: 100vw;
    }
    :root[sessionrestored] #urlbar[popover]{
    pointer-events: none;
    opacity: 0;
    transition: transform 82ms linear var(--uc-autohide-toolbox-delay), opacity 0ms calc(var(--uc-autohide-toolbox-delay) + 82ms);
    transform-origin: 0px calc(0px - var(--tab-min-height) - var(--tab-block-margin) * 2);
    transform: rotateX(89.9deg);
    }
    #mainPopupSet:has(> [panelopen]:not(#ask-chat-shortcuts,#selection-shortcut-action-panel,#chat-shortcuts-options-panel,#tab-preview-panel)) ~ toolbox #urlbar[popover],
    #navigator-toolbox:is(:hover,:focus-within,[movingtab]) #urlbar[popover],
    #urlbar-container > #urlbar[popover]:is([focused],[open]){
    pointer-events: auto;
    opacity: 1;
    transition-delay: 33ms;
    transform: rotateX(0deg);
    }
    #mainPopupSet:has(> [panelopen]:not(#ask-chat-shortcuts,#selection-shortcut-action-panel,#chat-shortcuts-options-panel,#tab-preview-panel)) ~ toolbox,
    #navigator-toolbox:has(#urlbar:is([open],[focus-within])),
    #navigator-toolbox:is(:hover,:focus-within,[movingtab]){
    transition-delay: 33ms !important;
    transform: rotateX(0);
    opacity: 1;
    }
    /* This makes things like OS menubar/taskbar show the toolbox when hovered in maximized windows.
    * Unfortunately it also means that other OS native surfaces (such as context menu on macos)
    * and other always-on-top applications will trigger toolbox to show up. */
    @media (-moz-bool-pref: "userchrome.autohide-toolbox.unhide-by-native-ui.enabled"),
    -moz-pref("userchrome.autohide-toolbox.unhide-by-native-ui.enabled"){
    :root[sizemode="maximized"]:not(:hover){
    #navigator-toolbox:not(:-moz-window-inactive),
    #urlbar[popover]:not(:-moz-window-inactive){
    transition-delay: 33ms !important;
    transform: rotateX(0);
    opacity: 1;
    }
    }
    }

    #navigator-toolbox > *{ line-height: normal; pointer-events: auto }

    /* Don't apply transform before window has been fully created */
    :root:not([sessionrestored]) #navigator-toolbox{ transform:none !important }

    :root[customizing] #navigator-toolbox{
    position: relative !important;
    transform: none !important;
    opacity: 1 !important;
    }

    #navigator-toolbox[inFullscreen] > #PersonalToolbar,
    #PersonalToolbar[collapsed="true"]{ display: none }

    /* This is a bit hacky fix for an issue that will make urlbar zero pixels tall after you enter customize mode */
    #urlbar[breakout][breakout-extend] > .urlbar-input-container{
    padding-block: calc(min(4px,(var(--urlbar-container-height) - var(--urlbar-height)) / 2) + var(--urlbar-container-padding)) !important;
    }

    /* Uncomment this if tabs toolbar is hidden with hide_tabs_toolbar.css */
    /*#titlebar{ margin-bottom: -9px }*/

    /* Uncomment the following for compatibility with tabs_on_bottom.css - this isn't well tested though */
    /*
    #navigator-toolbox{ flex-direction: column; display: flex; }
    #titlebar{ order: 2 }
    */