Why doesn't document.write work in Firefox?

Question

JavaScript

When I try to rewrite the content of the page, I get an error that it is unsafe: I
SecurityError: The operation is insecure.
run the code from the content script of my own browser extension.

Can you please tell me how can I use document.write in Firefox browser? Maybe there is some tricky setting in the browser configs that disables the ban? Or some special permission for extension manifest?

Answer 1

Thanks to Aetae for suggesting a solution that works in Firefox:

document.wrappedJSObject.write(''); document.close();

If you run the method from the content script in your extension even before the DOM is drawn, this will prevent the launch of site scripts, and then you can safely fill in your content on the page.