auto-hide bookmarks toolbar - firefox 80

just updated to firefox 80 and the autohide bookmarks toolbar function is broken. 

add in userchrome.css

here is the fix, 

#PersonalToolbar{
  --uc-bm-height: 20px; /* Might need to adjust if the toolbar has other buttons */
  --uc-bm-padding: 4px; /* Vertical padding to be applied to bookmarks */
  --uc-autohide-toolbar-delay: 600ms; /* The toolbar is hidden after 0.6s */
}

:root[uidensity="compact"] #PersonalToolbar{ --uc-bm-padding: 1px }
:root[uidensity="touch"] #PersonalToolbar{ --uc-bm-padding: 7px }

#PersonalToolbar:not([customizing]){
  position: relative;
  margin-bottom: calc(0px - var(--uc-bm-height) - 2 * var(--uc-bm-padding));
  transform: rotateX(90deg);
  transform-origin: top;
  transition: transform 135ms linear var(--uc-autohide-toolbar-delay) !important;
  z-index: 1;

}
#PlacesToolbarItems > .bookmark-item{ padding-block: var(--uc-bm-padding) !important; }

/* SELECT BOOKMARKS TOOLBAR BEHAVIOR */
/* Comment out or delete either one of these to disable that behavior */

/* Show when urlbar is focused */
#nav-bar:focus-within + #PersonalToolbar{
  transition-delay: 100ms !important;
  transform: rotateX(0);
}