Just two days ago I started seeing a "Click to continue" icon with various underlined words on some web-pages and Google search results. When I hover over it, I see that it's pointing to s.igmhb.com/click?vXXXXXXXXXXXXXXXXXXXXXX (with the Xs being a long string of letters and numbers).

I find nothing suspicious or recently added in Control Panel > Programs and Features.

I use Webroot SecureAnywhere and notice that it's removing 6 threats every time it scans, but clearly not this.

In searching for a fix I see many references to AdwCleaner, Bitdefender and Malwarebytes but am now overly fearful of installing something new.

How to I get rid of this garbage?