How to debug chrome extension at such part of code? - google-chrome-extension

Question

The code below is the JavaScript file works with popup.html from a small project.
I use it for chrome extension development learning.
The first part of this code piece is getting two variable from chrome storage, let's call it part1.
The second part is a button-click event function,Let's call it part2.
The button is on popup page and called "spend".
In part2, I can set a breakpoint2 on chrome debugger DevTools,when I click the button on popup page, it will stop at breakpoint2.
But when I place a Breakpoint1 at part1,the code will not stop at that line, even I add one more line "debugger;", the program will not stop there.
So my problem is how to make the debugger stop at places like breakpoint1?
The source code for the extension:https://drive.google.com/file/d/1odxJy9pGnovzox2yXH-6MDO03_T7QIDE/view?usp=sharing
//popup.js
$(function(){
chrome.storage.sync.get(['total','limit'],function(budget){
//Breakpoint1
$('#total').text(budget.total);
$('#limit').text(budget.limit);
});
$('#spendAmount').click(function(){
//Breakpoint2
chrome.storage.sync.get(['total', 'limit'],function(budget){
var newTotal = 0;
if (budget.total){
newTotal += parseInt(budget.total);
}
var amount = $('#amount').val();
if (amount){
newTotal += parseInt(amount);
}
chrome.storage.sync.set({'total': newTotal}, function(){
bla();
bla();
}
});
$('#total').text(newTotal);
$('#amount').val('');
});
});
});
Any assistance is highly appreciated,Thanks in advance.