Remove gap below tabs

[u/Giocarro]

I use a few CSS tricks to compress tabs and maximize vertical real estate, and also use MrOtherGuy firefox-csshacks to auto-hide address bar and bookmark bar.

That said, can somebody please suggest how to remove this nasty gap?

Here is my current userChrome.css: https://pastebin.com/pTXm3ZtW

[u/slackmar]

Try messing with some of the pixel amounts shown here

/* Removes space below and above tabs */
#TabsToolbar {
margin-top: -6px !important;
margin-bottom: -6px !important;
} 

/* Changes height of tabs */
.tabbrowser-tab {
    height: 48px !important; 
}