Linux oneliner + sidebar setup for Firefox/Librewolf/Firedragon

userChrome.css

#sidebar-box > #sidebar-header {
     visibility: collapse;
}

/* ABOUT:HOME - ABOUT:NEWTAB */
@-moz-document url-prefix(about:home), url-prefix(about:newtab) {
 body{
  --newtab-background-color: #242424 !important;
 }
}

.sidebar-splitter {
  /*display: none !important*/
  width: 1px !important;
  border-left: none !important;
  border-color: black !important;
}

#sidebar-box {
  position: relative !important;
  overflow:hidden;
  min-width: 30px !important;
}


body {

    /* dynamic url bar width settings */
    --uc-urlbar-width: clamp(200px, 40vw, 500px);

    /* dynamic tab width settings */
    --uc-active-tab-width:   clamp(100px, 20vw, 300px);
    --uc-inactive-tab-width: clamp( 50px, 15vw, 200px);
}
/* transition to oneline */
@media (min-width: 800px) {


    /* move tabs bar over */
    #TabsToolbar {
    margin-left: var(--uc-urlbar-width) !important;
        margin-top: -2px !important;

    }


    /* move entire nav bar  */
    #nav-bar {
        margin: calc((var(--urlbar-min-height) * -1) - 12px) calc(100vw - var(--uc-urlbar-width)) 0 0 !important;

    }

    /* Title bar */
    .titlebar-buttonbox {
        display: none !important;
    }

    .titlebar-spacer {
        display: none !important;
    }

    /* Tab bar */
    #navigator-toolbox {
        border: 0px !important;
    }

    #TabsToolbar {
        margin-left: 30vw !important;
    }

    /* Nav bar*/
    #nav-bar {
        background: transparent !important;
        margin-top: -36px !important;
        margin-right: 70vw !important;
        border: none !important;
    }

    /* URL bar */
    #back-button {
        display: none !important;
    }

    #forward-button {
        display: none !important;
    }

    #tracking-protection-icon-container {
        display: none !important;
    }

    #urlbar-container {
        min-width: 100px !important;
    }

    #urlbar {
        background: transparent !important;
        border: none !important;
        box-shadow: none !important;
    }

    #page-action-buttons {
        display: none !important;
    }

    #PanelUI-button {
        display: none !important;
    }

    /* adaptive tab width */
    .tabbrowser-tab[selected][fadein]:not([pinned]) { max-width: var(--uc-active-tab-width) !important; }
    .tabbrowser-tab[fadein]:not([selected]):not([pinned]) { max-width: var(--uc-inactive-tab-width) !important; }

}