FirefoxSidebar/firefox/userChrome.css

#main-window[tabsintitlebar="true"]:not([extradragspace="true"]) #TabsToolbar > .toolbar-items {
  opacity: 0;
  pointer-events: none;
}
#main-window:not([tabsintitlebar="true"]) #TabsToolbar {
    visibility: collapse !important;
}

#sidebar-box[sidebarcommand="treestyletab_piro_sakura_ne_jp-sidebar-action"] #sidebar-header {
  display: none;
}

/*Collapse in default state and add transition*/
#sidebar-box[sidebarcommand="treestyletab_piro_sakura_ne_jp-sidebar-action"] {
    overflow: hidden;
    min-width: 40px;
    max-width: 40px;
    border-right: 1px solid var(--panel-separator-color);
    z-index: 2;
}

/*Expand to 260px on hover*/
#sidebar-box[sidebarcommand="treestyletab_piro_sakura_ne_jp-sidebar-action"]:hover,
#sidebar-box[sidebarcommand="treestyletab_piro_sakura_ne_jp-sidebar-action"] #sidebar {
  min-width: 260px !important;
  max-width: 260px !important;
  z-index: 1;
  margin-right: -210px !important;
}

:root {
  --sidebar-width: 50px;
  --toolbar-height: -50px;
  --menubar-height: -75px;
  --toolmenubar-height: -80px;
  --sidebar-padding: calc(var(--sidebar-width) + 5px);
}


#main-window #PersonalToolbar {
    margin-left: var(--sidebar-width);
    padding: 2px 5px;
    padding-top: 0px;
    margin-top: -1px;
}

/* lock sidebar to height by doing the inverse margin of the toolbar element */
#sidebar-box {
  z-index: 1000 !important;
  position: relative!important;
  margin-top: var(--menubar-height) !important;
  border-right: 1px solid #ccc;
}

#main-window[title^="Firefox Developer Edition"] #sidebar-box {
  margin-top: var(--toolmenubar-height) !important;
}

/* lock sidebar to specified width */
#sidebar-box, #sidebar-box #sidebar {
    min-width: var(--sidebar-width) !important;
    max-width: var(--sidebar-width) !important;
}

/* hide sidebar header for tree style tabs sidebar */
#sidebar-box[sidebarcommand="treestyletab_piro_sakura_ne_jp-sidebar-action"] #sidebar-header {
  display: none;
}

/* Hide the title bar */
#titlebar{ visibility: collapse; }

/* hide normal horizontal tab bar */
#TabsToolbar { visibility: collapse; }

#sidebar { border-right: 1px solid #ccc; }

toolbar#nav-bar {
  padding-top: 12px;
  padding-bottom: 7px;
  margin-left: var(--sidebar-width);
  padding-left: 7px;
}

.sidebar-splitter {
  opacity: 0 !important;
  width: 0px !important;
  border: none !Important;
  --avatar-image-url: none !important;
}

:root:not([uidensity="compact"]) #back-button > .toolbarbutton-icon {
  border: none !important;
  background: none !important;
}

/* --- Prevent enlargement */
#urlbar[breakout-extend] {
    top: calc((var(--urlbar-toolbar-height) - var(--urlbar-height)) / 2) !important;
    left: 0 !important;
    width: 100% !important;
}

#urlbar[breakout-extend] #urlbar-input-container {
    height: var(--urlbar-height) !important;
    /*padding: 0px !important;*/
    padding-block: 0px !important;
    padding-inline: 0px !important;
}
.urlbarView-row {
    padding: 0px 2px 0px 2px;
}
/* END Prevent enlargement --- */

/*/* --- Reduce row paddings to make them more compact */
.urlbarView-row {
    padding: 2px 0px !important;
    line-height: 1.2em !imortant;
    margin: -1px;
    margin-bottom:0px;
}
.urlbarView-row-inner {
    padding-bottom: 6px !important;
}
.urlbarView {
    margin: 0px !important;
    width: 100% !important;
}
/* END Reduce row paddings to make them more compact --- */

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

/* --- More compact "Search with Google" rows */
.urlbarView-row[dynamicType="onboardTabToSearch"] > .urlbarView-row-inner {
    min-height: auto !important;
    width: auto !important;
}
.urlbarView-row[dynamicType="onboardTabToSearch"] > .urlbarView-row-inner > .urlbarView-no-wrap > .urlbarView-favicon {
    margin-bottom: -1px;
}
/* END More compact "Search with Google" rows --- */

 #nav-bar{ --toolbar-field-focus-border-color: #ccc }

.bookmark-item[container] {
    list-style-image: url("data:image/svg+xml;base64,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") !important;
  margin-right: 8px !important;
  }


.bookmark-item[container]::after {
    content: "ˇ";
    opacity: 0.7;
    padding-left: 3px;
    font-size: 22px;
    display: inline-block;
    position: absolute;
    top: 4px;
}