You will be warned in such a situation while using the Google DevTools console. This warning is as follows:
[Violation] Avoid using document.write().
Firefox DevTools provides similar feedback:
An unbalanced tree was written using document.write() causing data from the network to be reparsed.
When Google Lighthouse encounters this situation, it flags the page in question:
Lighthouse also removes the warning if different commands are used to provide the same function instead of such a command.
How to pass the audit? – Avoiding document.write()
You need to delete all document.write () snippets in HTML code. You can do the same by using the asynchronous loading function instead.