For those of you having fits with this bug from ITunes 12.7.4, be very careful when going back to 12.3.76. There's a bug in THAT version that breaks all favicons in Internet Explorer 11, EVEN IF you check the box in ITunes to REPLACE Favorites in the IPhone. Why, when you are copying FROM the computer, TO the phone, all of the favicons in Internet Explorer would be overwritten and replaced with generic icons, is beyond my comprehension. The only fix for this is to have exported your favions/favorites to an html file from within IE, then after ITunes ruins everything, go to the Favorites folder, delete all content in the subfolders, then import the favorites back into IE from your html saved file. This will happen every time you sync with ITunes, so get ready. Oh, and guess what: If you sync your Safari favorites with ICloud, the local PC is fine, along with the favicons, but Safari doesn't have any favicons.
And before everyone tells me that I should be using Edge, the EXACT same thing occurs with that browser as well. Even if you import Favorites from IE11, there are no favicons in Edge at all.
I guess we'll be told that we shouldn't "need" favicons next. And if you don't know what a favicon is, you don't care about what I have just said here. 😉
ITunes has become a complete mess over the past 6 months.