Thumbs up for trying!
Thing is you are looking out for a buff application, and you have a event for that that you can use (much better than having a OnUpdate script, because that runs each frame, not very necessary).
You need the event
UNIT_AURA, a frame to work with and since this is a UNIT_* event we can use
RegisterUnitEvent.
Code:
local f = CreateFrame("Frame")
f:RegisterUnitEvent("UNIT_AURA", "player")
f:SetScript("OnEvent", function()
if UnitBuff("player", "Molten Armor") then
ActionButton_ShowOverlayGlow(ActionButton1)
else
ActionButton_HideOverlayGlow(ActionButton1)
end
end)
ActionButton1 is only for the default action bar, if you use an addon then you need to /fstack and find the frame name of your button.