That is not possible.
It might not be exactly the same you want.
You can try debug with Chrome browser, in debugger windows, source,
In widget.js, you can modify what you want and save. (ctrl + s)
And continuing debugging until you get it right.
But make sure you copy back the code to your code editor because it will be gone after page is refresh.
That's what I always do and it works great. You should work with breakpoints and once you save any changes the code will jump back up and stop at a breakpoint. Google has a great tutorial with step-by-step on how to do it -
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