This is how it looks like on any page1 except the chat page:
The site icons are visible here, but on the chat page2, these icons seem to have disappeared (the alignment is messed up as well):
This also happens in the reputation and inbox dropdowns.
I'm using Chrome (version 102.0.5005.115) on Windows 11.
1 The dropdown is accessible by clicking on the icon in the rightmost corner of the top nav.
2 This can be accessed by clicking on the Stack Exchange button in the leftmost corner of the top nav on the chat page.