Previously I was having this issue also until I perform Google Chrome cache clean up. I saw some of the forumers also did that but still having it popup.

I suspect maybe is the step to do the cache clean up.

This is my steps:
1. Close the web page(s) that you are visiting, I mean all of them. If the popup is there, kill the Google Chrome until you able to close all the web pages before it popup.
2. Go to Google Chrome "Settings", "Privacy", and then select "Clear browsing data".
- Clear everything from beginning of the time.
- You can left "Save passwords" and "Autofill form data" un-tick if you want to preserve those information.
3. After that, exit Google Chrome and kill it from the Recent Task List.
4. Start Google Chrome again and test it. Should be ok.

I notice, the popup might be coming back once in a while, but at least the above steps able to remove the popup immediately without reseting your phone.
Don't clear Google Chrome cache while you still have web page open and running in Google Chrome as IT WILL NOT WORK, because while the web page is open, it will keep on asking the Google Chrome to remember those nasty "popup" in the memory.

This post has been edited by ckshieh: Oct 8 2016, 10:43 AM