Waiting for certain network calls to finish before taking action on the page

Hey Ethen! This mission is not impossible. I'm not as familiar with the python flavor of P-wright, but I do know the JS version well.

What I would (and have) done is to make a web-first assertion before taking the screenshot. That is, wait until the last item that loads into the page is loaded by asserting its visibility before taking the screenshot.

Modern JS frameworks are inherently asynchronous, and using networkidle is not recommended. The issue is this - if the network call succeeds, it shifts the layout of the entire page down enough to trigger screenshot mismatch failure. There is no web first thing to assert on.

""" When I implemented this using page.expect_response, it was not able to loop through a set of network calls and wait for them. """ How does that implementation using expect_response look?

Whenever I have to do screenshot comparisons, I'm using routeFromHar and updating the har file when updating the screenshot, you can give it a try. https://playwright.dev/python/docs/api/class-browsercontext#browser-context-route-from-har

if wait_for_response: for network_call in wait_for_response: try: url = network_call + ".*" pattern = re.compile(rf"{url}") with page.expect_response(pattern, timeout=40000) as response_info: print(f"INFO: {network_call}: has received response " + str(response_info.value.status) + " for " + str(response_info.value.url)) except Exception as e: print(f"FAIL: {network_call}: has NOT received a response.") raise e

What do you mean by "is not able to loop?" Does the loop throw an error, or does the loop complete without waiting?

So the content shifts but there is no element that is added or removed that causes the content shift?