In case you don't know yet, Google is working on a new user experience for downloads in Chrome, and now, in the Canary version, it is already possible to see the new downloads button in the toolbar.
When you click on the file to download, the new button appears in the toolbar:
Chromium developers have not yet added the bubble that will accompany the button so, for now, when you click on it, nothing happens. I think by default the bubble will be displayed along with the button when the download starts.
As I explained in the other post, the blue icon will have a progress ring in the future, that's why it now looks so "small" on the toolbar, It could be something similar to the progress ring in Edge's downloads button: