By the way, I decided to remove the full screen option and keep kepubs instead. However, deleting the line I had added to the configuration file, under FeatureSettings, was not sufficient to get me back to the original configuration. It seems the Kobo adds the same line to the Reading section and that has to be deleted as well.
(I don't think I've seen this mentioned in this thread but given my previous posting here, who knows...
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