Chrome will now (starting on M80) attempt to upgrade some types of mixed content (HTTP on an HTTPS site) subresources. Subresources that fail to load over HTTPS will not be loaded. For more information see the official announcement.
Currently only audio and video subresources are autoupgraded. On a future version images will be included.
Users can disable autoupgrades on a per-site basis through content settings (chrome://settings/content/insecureContent).