Google Chrome	66.0.3336.6 (Official Build) canary (64-bit) (cohort: 64-Bit)
Windows 10 Enterprise Version 1607 Build 14393.2007
NVDA 2017.4
JAWS 2018.1801.81 ILM 

This is related to a webpage authoring issue, this is not screen reader dependent. Both screen readers behaved the same so for simplicity, I'll just report the experience.

On Stable and Dev, the download button is labeled as a button
https://www.google.com/chrome/browser/desktop/index.html
https://www.google.com/chrome/browser/desktop/index.html?extra=devchannel&platform=win64

On Canary and Beta, the download button is labeled as a link
https://www.google.com/chrome/browser/canary.html
https://www.google.com/chrome/browser/beta.html

These should all be buttons or links depending on the intended semantics. Since it's visually a button, I assume it should be a button. As it, it's very confusing to screen reader users.