Animated favicons
Can Favicons be animated?
Sometimes. I'll investigate this more later.
Use the same favicon for multiple sizes
<link rel="icon" href="/favicon.ico" sizes="16x16 32x32" />
Dynamic favicons
No doubt, you've seen sites where the favicon changes to indicate what's happening on the site.
Yes, you could do that in Webflow, using script. However, make sure to keep your homepage icon consistent. Google doesn't appreciate it if you change that icon often.
Dark mode Favicons
Some cool stuff, shared by James Ross.
<link rel="icon" href="/favicon.ico" media="(prefers-color-scheme:no-preference)">
<link rel="icon" href="/favicon-dark.ico" media="(prefers-color-scheme:dark)">
<link rel="icon" href="/favicon.ico" media="(prefers-color-scheme:light)">
Special Favicon formats
All browsers support the .ico format
SVG favicons
SVG favicons are NOT widely-supported, but Chrome supports them, and it seems likely this will grow in the future.
<link rel="icon" href="favicon.svg" sizes="any" type="image/svg+xml">
This is intriguing in part because it allows for certain dynamic capabilities like color schemes. See Thomas Steiner's work.
Note that SVG may not be ideal at smaller sizes, since it will be reduced by the browser, so make certain you specify the variations you want for those smaller favicons.