Is there any chance to find source of javascript alert?

alert, javascript

Solution

I'd go with redefining window.alert right at the start of the code for this type of development purposes.

window.alert = function(e){ console.warn( "Alerted: " + e ); }

This will give You a line number for sure. ( Tested on chrome console )

Problem

I'm working in a large project that was developed for several years and had tons of code. Recently uninformative alert start to appear. It just says Undefined. I need to find the source of this alert. Is the any chance to make something like "breakpoint on alert"? I want to see the source of this alert. One possibility is to redefine alert function. I tried to make it in firefox without any success.

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