Today I filed a formal complaint against #YouTube with the Irish Data Protection Commissioner for their illegal deployment of #adblock detection technologies.
Under Article 5(3) of 2002/58/EC YouTube are legally obligated to obtain consent before storing or accessing information already stored on an end user's terminal equipment unless it is strictly necessary for the provisions of the requested service.
In 2016 the EU Commission confirmed in writing that adblock detection requires consent.
It could check if the ad is present in Dom maybe?
Or they just check the machine to see if the malware served in the ad is present.