TBB: hide favicon placeholders with userChrome.css
For reasons of privacy, Tor Browser never requests site favicons. So why not hide the pointless default favicon placeholders? Here is a small userChrome.css (goes into the profile's chrome/ folder) that removes them from every tab, the bookmarks toolbar, the bookmarks menu, and address bar autocomplete items. Tested and works on ESR 10 and 17.
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