How can I add a console.log statement to a JavaScript file on a live website?

I want to see print something in console so I can see the values, its a live website that I dont have control, its not mine.

Here is what I did.

  1. Went to SOURCES tab
  2. opened that Javascript file
  3. put console.log()
  4. clicked CTRL+S
  5. Then without re-freshing website, I clicked on that particular
    button on website, AJAX was sent, but no message in console

NOTE: that orange icone you see? it says “changes to this file were not saved to file system”

PS: I know I can see in XHR request payload but thats not I want, that is different data, I want see data at that specific point.

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