Multi-Page Navigation

Two very different kinds of "clicking a link"

Most links behave the way you'd expect: click it, and the page you're looking at changes to the new URL. But some links (usually the ones with target="_blank" in their HTML, or a "Open in new window" button) open a completely separate browser tab, leaving the original page untouched behind it. Your script needs to handle these differently, because in the second case, the page object you already had is now the *wrong* one, the new content is somewhere else entirely.

The code, piece by piece

page.locator("article.product_pod h3 a").first.click()
end_url = page.url

This is the ordinary case: clicking navigates the same page object to a new URL. Because .click() already auto-waits for the resulting navigation, page.url on the very next line correctly reflects the new page, not a half-loaded old one.

context = browser.new_context()
page = context.new_page()

A browser context is an isolated session inside a browser, its own cookies, storage, and set of tabs, similar to opening a private/ incognito window. A context can hold multiple pages (tabs) at once, which is exactly what we need for the popup case below. Earlier lessons skipped creating a context explicitly; browser.new_page() was quietly creating a default one for you.

with context.expect_page() as new_page_info:
    page.locator("a", has_text="Click Here").click()
new_tab = new_page_info.value

This is the important pattern for popups. context.expect_page() starts listening for a new tab to open *before* the click happens, inside the with block. If we clicked first and only afterward tried to find the new tab, we'd be racing against the browser, sometimes it would work, sometimes the new tab wouldn't exist yet, a classic source of flakiness (see Lesson 9). new_page_info.value is the actual new Page object once it exists.

new_tab.wait_for_load_state()

The new tab exists as soon as it opens, but its content may still be loading. Same idea as Lesson 9: wait for a real condition, don't guess.

tab_count = len(context.pages)

context.pages lists every open tab in this context, useful for sanity-checking how many tabs are open, or for finding one you didn't capture directly with expect_page().