Jint

Browser, context, and page lifecycle ​

The ownership tree is:

text
Browser
└── BrowserContext (cookies, localStorage, network position)
    └── Page (document, sessionStorage, engine, thread)

Browser.NewPageAsync() uses the default context. Use separate contexts for isolated sessions:

csharp
await using var browser = new Browser();
await using var alice = await browser.NewContextAsync();
await using var bob = await browser.NewContextAsync();

var alicePage = await alice.NewPageAsync();
var bobPage = await bob.NewPageAsync();

Pages in one context share cookies and origin-partitioned localStorage. Different contexts share neither. sessionStorage belongs to a page.

Each page starts on about:blank. A top-level navigation creates a new Jint engine and document on the same page thread. The previous document receives beforeunload, pagehide, and unload; pending document work is cancelled and the old engine is disposed. Page-level history, request history, and emulation state survive the engine swap.

Closing a page stops its workers and thread. Closing a context closes all its pages. Closing the browser closes every context. Calls made after closure fail rather than hanging.

csharp
await page.CloseAsync();
Console.WriteLine(page.IsClosed);

Prefer await using or explicit CloseAsync() so shutdown waits for page and worker threads to finish.