Solomon’s temple had windows, but they are mentioned only once, in 1 Kings 6:4.  Ezekiel’s description of the visionary temple uses the word “window” twelve times.

One can see out of, and look into, Solomon’s temple.   From Ezekiel’s temple, Israel can look out the twelve windows to the world, and the temple is opened to the world.

This seems new: How strange is it to have the temple wall perforated with windows?  Pretty strange, I suspect.  Temples are supposed to be closed-off holy spaces.  But Ezekiel wants to open the windows of heaven.