Favicon not showing up on admin pages on chrome

My favicon works normally on the main site (tradescantia.uk), but not on wordpress admin pages for Google Chrome.

I added the favicon using the theme customiser “site identity” option. Then when I noticed the problem, I also followed the instructions to add it manually (uploaded favicon.ico to the main site directory and theme directory, and added the shortcut icon link to header.php).

The favicon shows up correctly for admin pages in Safari. I haven’t been able to try other browsers, but I’ve tried Chrome on two different devices and it’s the same.

Why is this happening, and how do I fix it?

The page I need help with: [log in to see the link]