Sunday, November 18, 2018
Site Isolation is a large change to Chrome's architecture that limits each renderer process to documents from a single site.
Chrome can rely on the operating system to prevent attacks between processes, and thus, between sites. Note that Chrome uses a specific definition of "site" that includes just the scheme and registered domain. Thus, https://google.co.uk would be a site, and subdomains like https://maps.google.co.uk would stay in the same process.