You’re correct about first-party cookies being from the domain in the address bar, like a.com in your example. When a page from a.com includes a resource from b.com, and b.com sets cookies, those are considered third-party cookies.
In a scenario where you navigate to c.com, which includes a resource (e.g., tracking pixel) from b.com, without third-party cookie protection, b.com would indeed have access to the cookies it set previously while you were on a.com. However, with 3rd party cookie protection measures, the browser restricts this access. This can impact user tracking and privacy.
In the JavaScript world, this is often managed through mechanisms like the SameSite attribute for cookies and technologies like ITP (Intelligent Tracking Prevention) in browsers. Developers need to adapt their code to these privacy measures to ensure compliance and user privacy.
You’re correct about first-party cookies being from the domain in the address bar, like a.com in your example. When a page from a.com includes a resource from b.com, and b.com sets cookies, those are considered third-party cookies.
In a scenario where you navigate to c.com, which includes a resource (e.g., tracking pixel) from b.com, without third-party cookie protection, b.com would indeed have access to the cookies it set previously while you were on a.com. However, with 3rd party cookie protection measures, the browser restricts this access. This can impact user tracking and privacy.
In the JavaScript world, this is often managed through mechanisms like the SameSite attribute for cookies and technologies like ITP (Intelligent Tracking Prevention) in browsers. Developers need to adapt their code to these privacy measures to ensure compliance and user privacy.