Yep. Here's an enlargement of the icon:
While this is regrettable, it is a result of your own customization of your browser. With a black theme you will experience the exact same problem on every other website that uses a black icon with a transparent background, such as The Escapist and The Washington Post. The only way we can fix this for you is to add in a background color to the icon, but that will make it look worse for everyone else.
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