Check for mouseover existence before changing the tooltip's text

diff --git a/Modules/Text.lua b/Modules/Text.lua
index 8ac925b..fbb5d6a 100644
--- a/Modules/Text.lua
+++ b/Modules/Text.lua
@@ -631,6 +631,8 @@ local getGuild = function()
 end

 function mod:SetUnit()
+	if not UnitExists("mouseover") then return end
+
 	unitName = getName()
 	unitLocation = getLocation()
 	unitGuild = getGuild()