I\'m using the chrome://favicon/ in my Google Chrome extension to get the favicon for RSS feeds. What I do is get the base path of linked page, and append it to
chrome://favicon/
I inspected the website-icon in Chrome history page and found this simpler method. You can get the favicon url by --
favIconURL = "chrome://favicon/size/16@1x/" + tab.url;
Don't forget to add "permissions" and "content_security_policy" to Chrome. (https://stackoverflow.com/a/48304708/9586876)