Favicon loading animation and blank area

[huipengcheng]

When I use the native TST, every time I load a new tab, the loading animation is displayed. But I didn't figure out how to display the animation by modifying this CSS file.

In addition, for some tabs without a favicon, a blank area will appear, but the native TST may have a favicon, such as the "Add-ons and themes" page. I want to know why this is, or how to replace the blank area with a default icon.

Thank you so much.