Favicon request code was removed (as of version 3.0.3). No single request is created from within the addon toward a third-party server. Favicons are directly taken from the sites that you visit (so each favicon from it's respective site and cached locally if possible).

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Hi. I care really a lot about privacy and I really messed up this. Since there was no way around to get links favicons using WebExtensions I looked up for alternatives and I found that google has a service for this. I'm really really sorry about this. When I read your message I literately stopped for 2 seconds realizing how idiot I've been that I thought this is an alternative solution. Really really sorry for doing this. And no, of course I'm not paid by google. I simply made a stupid decision without realizing that service may be tracked by google.
I really understand your concern and it's totally right.
Again.. really really sorry. The code will be removed right away. I will update the message as soon as I fix this.