How can I change the icon of my browser extension for the extension menu list?

Im coding a chrome browser extension and I have the problem, that I can not change the icon of the extension. I add the icon in the manifest.json and I can also see it when I click in the browser menu bar on "Extensions". But when I go in the browser on "Menu" > "Extensions", then theres no icon. Please help me

I searched already in the Internet but I don´t found anything. I added in the manifest.json with "default_icon", the icon, but the icon only appears in the browser tabbar list.

>Solution :

• Set icons key in manifest.json.

{
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  }
}