Yea, I have that as well, and it just started today. I'm not sure what it is but a weird ad pops up sometimes when I click on something, like when I clicked to reply a post here. Not sure what it is, but I'll be keeping an eye on it
EDIT: I got the ad again. I'm not sure what it is considering it just started showing up literately a minute ago while I searched around the forums. It's something called Search Incognito, and says some weird stuff about my Chrome browser.
It says this exactly.
Recommended: The Search Incognito extension protects your privacy by detecting searches that may be tracked and tied to your personal information. It intercepts those searches and redirects them to Search Incognito's privacy-enhanced search engine.
I'm not sure if this is related at all, but since that G just became a recent occurrence for me along with this ad which only appears on this forum, I'm assuming it has some correlation.