Description :

Using the command make:subscriber with an event suscriber kernel.controller on the interactive mode (Responding to the 'What event do you want to subscribe to?' question).
Submited : kernel.controller
Result : kernel.controller_arguments

Console :

Result :

Bug caused by :

When puting an Enter character on the console, a last check is made to verify even the character is a new line \n or a tabulation \t, then choose the returned autocomplete from the matches array with an $ofs = 0 which return $matches[0] = 'kernel.controller_arguments on the following lines :