[Replicant]

This is for the first tab, change f code to whatever icon you want. Increment the 2 in parenthesis by 1 for each tab. You need a line like this for each tab.

#channel-tabbar > ul > li:nth-child(2) > a:before {content: "\f221";}

Keep in mind that with this code, if you have tabs that are only visible to logged in users, those tabs will need to be after the visible to guest tabs or it won't work. This is because we don't have a unique identifier for each tab, so we are selecting them in numerical sequence.