Uploading a Favicon
Favicon is short for “favorite icon,” and refers to the little icon on the tab of each browser page.
Depending on the browser, the favicon also appears in address bar, just before the URL.
Favicons are generally 16 x 16 pixels or 32 x 32 pixels in size. Although Magento accepts .ico,
.png, .jpg, .jpeg, .apng, and .svg file types, not all browsers support these formats. The most
widely-supported file format to use for a favicon is .ico. There are many free tools available
online that you can use to generate an .ico image or convert an exiting image to the .ico format.