Curious about overflow property of html and body element


#1

Recently, when I tested my page using chrome, I found that I could not scroll down pages. However I performed normally when testing on mobile devices. After investigating ionic css files, I found the reason why I could not scroll vertically is that the overflow property of html and body element was set to hidden. So, I am very confused why should the html and body overflow hidden. I can understand why overflow-x should be hidden. But why overflow-y? Is there someone can help me out of this? Thanks in advance.