The developer used TopbarPlus v2 to achieve that:
local Icon = require(game.ReplicatedStorage.Icon)
-- Leftward icons
Icon.new()
:setName("Emotes")
:setImage(emoteImageId)
Icon.new()
:setName("Refunds")
:setImage(refundImageId)
:setLabel("Refunds")
Icon.new()
:setName("Booths")
:setImage(boothsImageId)
:setLabel("Booths")
-- Rightward icons
Icon.new()
:setName("Codes")
:setImage(codesImageId)
:setLabel("Codes")
:setRight()
Icon.new()
:setName("Settings")
:setImage(settingsImageId)
:setRight()