Brief summary for those in a hurry:

GHCQ and CSEC sniffed unencrypted analytics data in order to uniquely identify individuals. This capability was present at least 4 years ago. The analytics data included, among many others, Google's Admob, which remains unencrypted by default, states the article.

The slides show the same light-hearted treatment of people's privacy as in previous disclosures. Perhaps this could be explained by the agencies believing themselves to be 'good guys' targeting 'bad guys', but IMO it just reveals their naivety and/or culture of arrogance.