Certainly, you can either edit the popups (ALT+P) section in script editor, or use remote (ALT+R) scripts like this one:
Code
menu channel {
  $iif(!$isfile($chan(#).logfile),$style(2)) View channel log:logview $qt($chan(#).logfile)
  Random example:echo -a Hello world!
}
If the log file doesn't exist, the menu entry will be grayed out.

/help menus