Hi Bob. There has likely been no answer because we don't have an answer to your question at this time. Like the 'likes' feature, adding a dark theme for the desktop version is also considered a wish list item so it does not rank as high in priority as site fixes. Since our teams are busy handling a back log of issues that have resulted from the site migrations and HTTP implementation, we've had all hands on deck to take care of those issues. That means that wish list items must be put on the back burner until the migration issues are sorted.
Once we have any kind of info or update on the status on the dark theme, we'll be sure to let the site know. Thanks for your ongoing patience on the matter!