This is just something I noticed while browsing the wiki. I was looking at a series from the 1940s called Wow Comics, which was most notable for featuring Mary Marvel for most of its run. What struck me as interesting was the appearance of Mary Marvel on the cover over her first four appearances until afterwards:

After being essentially a miniskirt, the skirt went back to knee length where it stayed for most of the remainder of the series:

Even staying near knee length when upside down:

It is pretty different from the modern version, which is more like the length of the original: