Steps to reproduce:

1. Start the rrweb recording process
2. In your main tab navigate to https://edition.cnn.com/travel/article/qantas-project-sunrise-worlds-longest-flights-intl-hnk/index.html
3. Open the page in the new tab by clicking on the link was still a priority for Qantas. Do not switch to newly opened tab.
4. Open the page in the new tab by clicking on the link connecting Melbourne and Dallas. Do not switch to the newly opened tab.
5. In your main tab observe development console errors and page performance.

Actual result: The page hangs, and within a few navigations, it crashes. rrweb exceptions are an observer in dev. console. Error happening due to processing element that doesn't exist in the document.
Expected result: The performance should not be impacted. Logic should better detect cases where an element doesn't exist in the document.