I am not sure what kixtart function I should be looking for here.

I have written a script that checks the registry for the Version of Firefox installed and it returns this value, which is what I want - PC01 Firefox 75.0 (x64 en-US)

$ReturnValue = ReadValue("HKEY_CURRENT_USER\SOFTWARE\Mozilla\Mozilla Firefox", "CurrentVersion")

IF Open( 3 , "c:\profiles\firefox.txt" , 5 ) = 0
  $x = WriteLine( 3 , "%ComputerName%" + " Firefox " + $ReturnValue + @CRLF)
  IF Close(3)
    ? "Error closing file!"
  ? "failed to open file, error code : [" + @ERROR + "]"

I know that I have done this some years ago where I was in the past able to tell the script to only write the computer name and status once, just updating that line each login, but I can't remember what I did. I guess I need to use Readline to find the line and overwrite it, but there doesn't seem to be a command to delete that line and rewrite it. So I must have done it differently. Once I have it working, I will change the location to somewhere on the server.