Here are the Gwydir Street Festive Windows, plus a few from Upper Gwydir Street and Edward Street, as I wasn't sure if they were part of it or not. There were a couple in Gwydir Cottages, which definitely was part of the Gwydir Street sequence. At the bottom are a few particular good ones from other streets.
Click here for other decorated windows.
Click on a photo for a larger version.
A lot of the windows looked better at night! Here is a (small) photo of one of them:

As I said, several streets around Cambridge had the same idea. Here are some splendid ones from Ainsworth Street. Click for larger photo.
A window of viruses, with closeup, to admire them better
Window for day 10, set as a puzzle. The answers were given later.
Not a festive window but relevant to the times.