Recently Squarespace updated positions of menu, so you can follow these steps to change Favicon on All Pages.
At the end of this post I also share the code to change favicon on One Page, but it doesn’t really work well on all browsers.
#1. What is Favicon?
Favicon will appear here
and on Google Search Result.
#2. Click Settings on the left screen of the Edit mode
#3. Click Favicon on right side
#4. Click on the plus icon (+) to add your Favicon
#5. To change Favicon on One Page, you can use this code to Individual Page Header Code Injection.
Replace example favicon url with your desired favicon url.
<link rel="icon" type="image/png" href="https://us1.discourse-cdn.com/flex020/uploads/elfsight/optimized/1X/3de412869aafdcf69af73ff5c11a000f8801eb20_2_32x32.png">
<link rel="apple-touch-icon" type="image/png" href="https://us1.discourse-cdn.com/flex020/uploads/elfsight/optimized/1X/9281586c988083a3a8bbfe1425712114d8df738b_2_180x180.png">