Yeah, this is annoying and hop they update soon

I have a fix that we have implemented as a workaround for now.

Add this in the custom JS field and change the image url to the image you want for a favicon

<script>var faviconURL = 'add your image url here'

var link = document.querySelector("link[rel*='icon']") || document.createElement('link');

link.type = 'image/x-icon';

link.rel = 'shortcut icon';

link.href = faviconURL

document.getElementsByTagName('head')[0].appendChild(link);

</script>

Hope this helps