how to get rid of a pop-up msg: image8.pubmatic.com

bjz2007 2018-10-19 06:34:15 ( reads)

最近,  我上 yahoo.com的时候,    屏幕下面总是 pop up 一个 msg:

" Do you want to open or save ImgSync from image8.pubmatic.com        Open -- Save -- Cancel "

请问这个是什么?  我总是选 "Cancel",    可是,  这个 message  老是 pop up.      请教  如何 remove this pop -up?

Thanks in advance.