Global hook to change chat font size?

Is there a easy way to change chat font size? Globally?

 

I understand OnPlayerChat but why OnRunCommand?

 

Bcs OnRunCommand you can use "chat.say" ...
OnPlayerChat gets called from the command "chat.say"

 

I sort of get it,

Code:

function PLUGIN:OnRunCommand(arg)
   
    local msg = arg:GetString(0)
   
    if (msg ~= nil) and (msg ~= "") then print("DEBUG: " .. msg) end
   
   
end        

it prints only what players said, i dont see chat.say in the msg variable...how i would i know if its a chat.say ?

 

if arg.cmd.namefull == "chat.say"