This is one of the smaller changes to Google – at least if measured in pixels! Google changed their “Favicon.ico”, the 16x16 image file that usually shows in the browser address bar or in bookmarks. The old icon used a square with red, green and blue edges, wrapping an upper-case “G”. The new logo is a bit more open, showing just the lower-case blue “g” from the Google logo, without borders, and a bit of shadow. To see this, visit Google.com (or images.google.com, Google Product Search and so on), empty your browser cache and reload the page.
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