Stopping a page redirect to look at JavaScript console

I am currently assisting another developer troubleshoot an issue he's having. In the code, there is a JavaScript function call tied to the onclick event of the HTML link. Because the JavaScript code is failing, the page is redirecting before I have a change to look at the console log to see what the error is. One solution is to use a breakpoint in the code and that's what I'll ultimately do. But I found this great hack.

window.addEventListener("beforeunload", function() { debugger; }, false)

By running this code in the console first, it will pause execution and allow me to see the error in the console.