Sometimes when working on a large program I want to repeatedly save interim versions, so that it's easy to go back one version if I mess something up. Today I noticed a convenient way to do that with GlowScript programs. Just click "Download" and a copy will be sent to your download folder. Moreover, every time you do this, without deleting old downloads, the file name gets a number added, so you get a time-ordered set with names like test.py, test(1).py, test(2).py, etc. Convenient.
Bruce