wait_for_selector follows your timeout

The wait_for_selector option used to wait for 30 seconds and then load the page a second time, whatever timeout you set. Now:

• It follows timeout. The API waits for the element until shortly before the request’s timeout. If you don’t set timeout, it waits up to 60 seconds, for asynchronous requests too.
• One page load. The API doesn’t load the page a second time after that wait.
• A clear error. If the element doesn’t appear, the timeout_error message says so, with the number of seconds it waited.

An element that needed the second page load to appear won’t be found anymore. If that’s your case, check the selector or wait for an element that the first load adds.