Computer Configuration > Administrative Templates > Google Chrome > Content settings
Both
HKLM\Software\Policies\Google\Chrome
Allows you to set a list of url patterns that specify sites which are allowed to display blockable (i.e. active) mixed content (i.e. HTTP content on HTTPS sites) and for which optionally blockable mixed content upgrades will be disabled. If this policy is left not set blockable mixed content will be blocked and optionally blockable mixed content will be upgraded, and users will be allowed to set exceptions to allow it for specific sites. For detailed information on valid url patterns, please see https://cloud.google.com/docs/chrome-enterprise/policies/url-patterns. Wildcards, *, are allowed. Example value: https://www.example.com [*.]example.edu