The call to window.stop() stops HTML parsing/rendering, which is unnecessary since the script has downloaded the page via HTTP and will decompress it as-is as a binary file (zip.js supports concatenated payloads before and after the zip data). However, in my case, the call to window.stop() is executed asynchronously once the binary has been downloaded, and therefore may be too late. This is probably less effective than in your case with gtwar.

I implemented this in the simplest way possible because if the zip file is read from the filesystem, window.stop() must not be called immediately because the file must be parsed entirely. In my case, it would require slightly more complex logic to call window.stop() as early as possible.

Edit: Maybe it's totally useless though, as documented here [1]: "Because of how scripts are executed, this method cannot interrupt its parent document's loading, but it will stop its images, new windows, and other still-loading objects." (you mentioned it in the article)

[1] https://developer.mozilla.org/en-US/docs/Web/API/Window/stop

Edit #2: Since I didn't know that window.call() was most likely useless in my case, I understand your approach much better now. Thank you very much for clarifying that with your question!