So while not showing attributions on featured snippets was a bug, in that same screen shot, Google not showing favicons is not a bug - it was intended. Danny Sullivan from Google confirmed on Twitter that "lack of favicons is not a bug here." "With some browsers we show a simpler results format." he added.
Google added favicons to the mobile results about a month ago, which was upsetting to many in our industry.
Here is the screen shot from Firefox mobile on Android not showing favicons:
At first, Danny Sullivan thought that this was a bug - in fact, citing the lack of favicons as an explanation and rational for why Google not showing attribution is a bug. But it turns out the attribution bit was a bug, but the lack of favicons was a feature.
Here is Danny's tweet citing the favicons was a feature:
BTW, lack of favicons is not a bug here. With some browsers we show a simpler results format. But that simpler format does not mean we drop attribution links in Knowledge Panels -- those links should be there, and we'll get that fixed.
— Danny Sullivan (@dannysullivan) June 25, 2019
Here is his original tweet about how the favicons might have been a bug but later saying it was not a bug:
We didn't say this is a "test" nor do I think it is. I think it might be a glitch happening only in Firefox on mobile. I can replicate it there & only there. Notice that favicons also aren't showing as is normal with Chrome (as shown below) or Safari. I'll pass it on to check. pic.twitter.com/J9zsqqyD24
— Danny Sullivan (@dannysullivan) June 25, 2019
So now if you don't see favicons showing up in some browsers, it is not a bug but a real feature.
Forum discussion at Twitter.