I have a website running across multiple subdomains and each one has a favicon.ico icon file in the root of each subdomain. Each icon for each subdomain is exactly the same. Is there an easy way I can declare every icon but one with rel canonical? Or is it worth redirecting users to the original icon even though each icon is about 900 bytes?
I wouldn't be concerned about duplicate favicons - it is common across many sites to have duplicates.I would not action canonicals or redirects as it is not likely to have any SEO impact.