userChrome-linux.css

#navigator-toolbox {
  border-top-left-radius: 4px;
  border-top-right-radius: 4px;
}

#TabsToolbar {
  background-color: var(--toolbar-bgcolor);
}

.tabbrowser-tab {
  visibility: collapse;
}

.titlebar-button {
  height: 48px;
}

#toolbar-menubar {
  max-height: 28px;
}

#nav-bar {
  height: 48px;
  display: flex;
  flex-direction: row;
  align-items: center;
  margin-top: -48px ;
  margin-right: 100px;
}

[uidensity="compact"]:root .titlebar-button {
  height: 48px;
}
[uidensity="compact"]:root #nav-bar {
  margin-top: -48px;
}

#main-window[inFullscreen="true"] #sidebar-box,
#main-window[inFullscreen="true"] #sidebar-box + splitter {
  visibility: collapse;
}

#sidebar-box #sidebar-header {
  display: none;
}

#urlbar {
  --urlbar-height: 32px !important;
  --urlbar-toolbar-height: 40px !important;
}