Now a command (like help) which accepts a known fixed set of non-option arguments can simply set the bash variable fixedWords and have them expanded. All other commands fall back to default expansion unless the current word starts with a '-'.
This avoids our need for the extglob shopt. It also allows us to add more such fixed wordlist commands in the future. There might be a slight performance impact as the case distinction is now executed even for the completion of non-option arguments, but that shouldn't be noticable.