I want to know the answer to the following question:
Who used to make window panes?
All the background I'm provided with is that "The reason for the observation is that in the past, when panes of glass were commonly made by glassblowers, the technique used was to spin molten glass so as to create a round, mostly flat and even plate (the crown glass process, described above).". Is that enough to answer the question?
Answer: yes