What is missing is called the Google Sheets “sheets bar”.
This link rounds up many explanations. It turns out that the first Recommended Answer Below (zooming or window placement) fixed my problem so I can now use Tiller in my Chrome browser, but this may be of possible help to others in the future.
Thanks all. I regret the bandwidth I used exploring this. If an editor wishes to chop and channel this topic, I am fine with that.
Best!
Larry