How to debug

go to chrome://extensions/, and then click Service Worker
Right-click on your icon, click Inspect popup on your browser, and then find your source start debugging.

use the chrome.scripting.executeScript.runtime function

and you can directly inspect (F12) on the webpage. Click the Console tab, it will show you a source id(for example VM87:3) You can click it, and then start debugging.

chrome/tutorials/extensions/console-alert/static/js/main.js

Lines 5 to 16 in d04f38c

    
           chrome.storage.sync.set({msg: cmdName}) // You can not get the context on the function, so using the Storage API to help you. // https://developer.chrome.com/docs/extensions/reference/storage/ 
        
           chrome.tabs.query({active: true, currentWindow: true}).then(([tab])=>{ 
        
             chrome.scripting.executeScript({ 
        
               target: {tabId: tab.id}, 
        
               function: () => { 
        
                 chrome.storage.sync.get(['msg'], ({msg})=> { 
        
                   console.log(`${msg}`) 
        
                   alert(`Command: ${msg}`) 
        
                 }) 
        
               } 
        
             }) 
        
           })

Getting variables outside executeScript in chrome extension: https://stackoverflow.com/a/68622659/9935654

	chrome.storage.sync.set({msg: cmdName}) // You can not get the context on the function, so using the Storage API to help you. // https://developer.chrome.com/docs/extensions/reference/storage/
	chrome.tabs.query({active: true, currentWindow: true}).then(([tab])=>{
	chrome.scripting.executeScript({
	target: {tabId: tab.id},
	function: () => {
	chrome.storage.sync.get(['msg'], ({msg})=> {
	console.log(`${msg}`)
	alert(`Command: ${msg}`)
	})
	}
	})
	})