It was happening about a month or a few weeks ago for me when I was on Mibbit. A couple other people too mentioned it. Well before the sync, obviously.
There was also a banner ad on SWC that had that happen about 2 weeks ago, but that's since gone away. Selatos scrubbed the banners and didn't find anything - was probably coming from the Google Ads and they've nipped it now.
The Sync happening is just a coincidence.