What is the grey circle with down arrow 1/4 down from top right that won't go away

[Android Central Question]

This grey circle appeared after an add played on Chrome and it won't go away, even when I closed Chrome. It stays on the screen in front of everything else, including gmail, Google search, and the background.

What is it? Is it harmful? How do I get rid of it? Btw...i have a Samsung galaxy tab s2 running Android 7.

Thank you.

 

[B. Diddy]

Welcome to Android Central! Show us a screenshot: http://forums.androidcentral.com/ge...ide-how-post-screenshots-android-central.html. You'll have to register on this forum first. https://forums.androidcentral.com/a...in-android-central-community.html#post3754828