Possibly. There was this HN news article from a short time ago [0] "The vast majority of the favicons offered up by websites are PNG. 71.6% of <link rel=”icon”

Possibly. There was this HN news article from a short time ago [0] "The vast majority of the favicons offered up by websites are PNG. 71.6% of <link rel=”icon”> images are PNG. 21.1% of /favicon.ico files are secretly PNGs, including Reddit’s. Strangely, only 96.1% of Apple touch icons are PNG. Presumably the other 4% are broken." [0] https://news.ycombinator.com/item?id=28933391 https://news.ycombinator.com/item?id=28933391