When you bookmark a website, a neat little icon appears in the bookmarks list along with the site name. Browsers use the website favicon as the icon for the bookmark. However, when a bookmarklet is added to the Bookmarks toolbar, it usually has no icon or simply takes on the default bookmark icon for the browser. Now, if you are on Firefox, you can easily change this ugly icon with any image you want using an add-on.
To set a custom favicon to a bookmarklet, right-click on it, select “Change Favicon” from the menu, and select a ICO file saved on your computer. In addition to ICOs, the extension supports various other file formats like JPG, PNG, GIF, and BMP. And the cool thing is that you can select image of any size. The extension will automatically resize and convert image to desired 16×16 pixels PNG image.
Once the favicon is set, you can delete the source file from your hard disk.
If ever you wanted to change the icon again, follow the same procedure you did while setting it the first time.
Bookmark Favicon Changer can also change icons of Bookmark menu, Bookmark toolbar, Bookmark sidebar, and Bookmark manager. To remove or reset icons to default state, right-click on the desired item and choose “Remove Favicon” or “Reset Favicon” menu option respectively.
It’s a free extension, and works will all flavours of Firefox. Follow the link below to download it from the official repository.
Download: Bookmark Favicon Changer