Lets you replace a bookmark's icon / favicon. Right click any bookmark, select "Properties", then "Browse". (Mac users do this from the bookmarks sidebar - Command+B). Features: --> works with many image formats (jpg, gif, png, bmp, etc) as well as .ico files. --> any image size can be used (they still display as the small size). --> get images from a url (Windows only) - click "Browse" and paste
![Favicon Picker 3 :: Add-ons for Firefox](https://cdn-ak-scissors.b.st-hatena.com/image/square/7e3cc0e6190c6b8934f30558494972fdf871cb7a/height=288;version=1;width=512/https%3A%2F%2Faddons.cdn.mozilla.net%2Fuser-media%2Fpreviews%2Ffull%2F22%2F22771.png%3Fmodified%3D1530208376)