How to get tab/url's favicon in safari web extension natively?

I'm converting a Chrome Extension to a Safari Web Extension, I found it's not easy to get favicon of current tab/url natively.
  1. The tab object in Safari doesn't have favIconUrl.

Code Block json{  "id": 121,  "index": 6,  "active": true,  "width": 1324,  "audible": false,  "url": "https://github.com/",  "mutedInfo": {    "muted": false  },  "windowId": 2,  "title": "GitHub",  "incognito": false,  "pinned": false,  "height": 935,  "highlighted": true,  "status": "complete"}    

2. I didn't find Safari has similar thing like chrome://favicon

3. I found Safari's favicon caches in ~/Library/Safari/Favicon Cache/favicons but have no idea how to use them in Safari Web Extension.

Am looking for FavIcon API too, where I can change them from safari extension. Best would be to get data_uri-mime-base64 type image of favicon and possibly way to write it back.

Has anything changed since then?

How to get tab/url's favicon in safari web extension natively?
 
 
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