userChrome.css

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

/* hide the scroll bar on the vertical tabs */
#sidebar {
  /* margin-right:-17px !important; */
  margin-bottom:-23px !important;
  overflow-y:scroll;
  overflow-x:hidden;
}

/* to hide the sidebar header */
#sidebar-header {
    visibility: collapse;
}


/* Tridactyl minimal CSS
 *
 * Contributors: aplaice, Oliver Blanthorn, Colin Caine
 *
 * Move this file to %appdata%/Mozilla/Firefox/[your-profile]/chrome/userChrome.css
 * Currently, it reduces the amount of padding around the UI, removes the tab bar
 * and autohides the navigation bar. If you want to drag the window around press
 * "alt" and then use the menu bar to move it, but you're better off pressing
 * the Windows key + an arrow key to move the window where you want it.
 *
 * If you're not on Windows, you can find your profile folder on
 * about:support
 *
 * Borrowed from https://www.reddit.com/r/FirefoxCSS/comments/73359a/my_firefox_57_setup/?utm_content=title&utm_medium=browse&utm_source=reddit&utm_name=FirefoxCSS
 *
 * This file is a work in progress.
 *
 * Any information on where to find documentation on valid properties we can edit here would be appreciated.
 *
 */


/* auto-hide the tab and navigation bar in a similar way to fullscreen mode */

/* User config */
/* #navigator-toolbox {*/
/*     /* The height of the area at the top of the screen that causes the nav-bar to be shown*/
/*     If zero, you can still focus with <C-l> or F6.*/
/*      */*/
/*     --tridactyl-auto-show-zone: 10px;*/
/* }*/

/* Hide grey container box */
:root:not([customizing]) #navigator-toolbox:not(:hover):not(:focus-within) {
    max-height: 0;
    min-height: calc(0px); /* I have no idea why just using 0 or 0px does not work... */
}

/* Auto hide tab bar */
:root:not([customizing]) #navigator-toolbox:not(:hover):not(:focus-within) #TabsToolbar {
    visibility: collapse;
}

/* /1* Auto hide nav bar *1/ */
/* :root:not([customizing]) #navigator-toolbox:not(:hover):not(:focus-within) #nav-bar { */
/*     max-height: 0; */
/*     min-height: 0!important; */
/*     /1* Use margin-bottom to allow trigger zones that are larger than the nav-bar *1/ */
/*     margin-bottom: calc(-1 * var(--tridactyl-auto-show-zone)); */
/*     opacity: 0; */
/* } */

/* Avoid transparent background for menubar if nav-toolbox not focussed */
#navigator-toolbox:not(:hover):not(:focus-within) #toolbar-menubar > * {
    /* Colour matches the grey background of the default firefox theme. Can't see what variable it uses */
    background-color: rgb(232, 232, 231);
}


/* Make top bar more compact */

/* Make nav-bar thinner */
#nav-bar{
    padding-top: 1px !important;
    padding-bottom: 0 !important;
}

/* We need more padding when maximised (maybe just on Windows?) */
#main-window[sizemode="maximized"] #nav-bar{
    padding-top: 7px !important;
}

/* Hide URL notifications that aren't particularly useful and cover up the command line
 * TODO: move it above the command line / bring functionality into status line like Vimperator */
statuspanel[type="overLink"]{display: none !important;}

/* Partial removal of black bottom 1px line shown in fullscreen mode */
#navigator-toolbox::after { display: none !important; }

/* Kill tab bar */
#TabsToolbar { visibility: collapse; }

/* Remove window decorations (Close, Minimize, Fullscreen) */
/* XXX: this makes things blow up:
#titlebar { display: none !important; } */
#TabsToolbar .titlebar-placeholder { display: none !important; }