Chrome extensions transforming into adware
Recent incident:
Such trickery has been going on for years. Google changed its policy back in 2014 so that extensions could only be ‘single purpose’ but that hasn’t stopped it.
Reality is, although Chrome does prompt the user to accept new permissions if a previously innocuous extension has been updated to introduce advertising functionality, the typical end user won’t understand what they are agreeing to. And, if the extension already has the required permissions, there is no prompt.
Apparently the seller of Particle signed a non-disclosure agreement, so we don’t know who the bad actor is.