The problem is related to a “malicious ad” that was able to get into the Google advertising network. The ad would trigger the popup as you browsed your favourite
websites (including CFF). The ad has been removed, but if you’re still experiencing problems, the best way to make sure you don’t see this malicious ad again is to clear
your cookies, cache, and browser history.
Here’s how to do that in Chrome for Android:
Navigate to Chrome’s Privacy tab by going to the Triple Dot menu button (upper right-hand corner) > Settings > Privacy.
Once inside the Privacy tab, tap on “Clear browsing data” (the large button at the bottom).
How to clear cookies, cache, and history in Chrome for iOS:
Open Google Chrome on your iPhone or iPad, tap on the Triple Dot menu and click on “History.”
Click on “Clear Browsing Data …”
Select which browsing data to clear (“Browsing History,” “Cookies, Site Data,” “Cached Images and Files”), then tap on “Clear Browsing Data” at the bottom.
How to clear cookies, cache, and history in Safari for iOS:
Launch the Settings app from the home screen of your iPhone or iPad. Scroll down and tap on Safari.
Scroll to the bottom and tap on “Advanced.” Tap on “Website Data.”
Scroll to the bottom again and tap on “Remove All Website Data.” Confirm again you’d like to delete all data.