Rendering Context Properties

SEO

Type: boolean (read-only)

Whether the page is rendering for a search engine crawler.

It's set for each page request, not by a site setting. It doesn't change while your code runs.

Example

SSR

Type: boolean (read-only)

Whether the code is running without a browser window, such as while the page renders on the server.

This is true wherever there's no global window, which includes a web worker as well as the server. It's false in a browser window.

It doesn't change while your code runs. It stays true for the whole server render, and false for as long as the page is open in the browser. Don't use it to choose what a component renders, because the server HTML won't match the browser render. Put browser-only work in an effect or an event handler instead.

Example