Healthbar Execute addon

Janusm

Is there any Execute addon that show execute icon on enemy healthbar that is above their head ? Lets say something like this.

Just quick photoshop from random pictures found

Im personaly using realy minimalistic UI (the one from picture is not mine) and becouse of that i sometimes have problem to get exact time of execution coz im more focused on ground (to avoid AoE) and enemy model than on the top hp bar, becouse of that i sometimes start to execute a bit to late what couse obvious DPS lose.