Custom Tooltips is a WoW AddOn to display custom tooltips for your macros.

Add tooltips at the top of core.lua and display them in your macro by adding #customtooltip TooltipName to the macro.

You can also define your tooltips in the macro itself using #tooltipdesc Heading Text^Body Text somewhere in the macro.

You can download the AddOn from CurseForge or WoWInterface.