  Web cookies have been the subject of many research studies over the last few
years. However, most existing research does not consider multiple crucial
perspectives that can influence the cookie landscape, such as the client's
location, the impact of cookie banner interaction, and from which operating
system a website is being visited. In this paper, we conduct a comprehensive
measurement study to analyze the cookie landscape for Tranco top-10k websites
from different geographic locations and analyze multiple different
perspectives. One important factor which influences cookies is the use of
cookie banners. We develop a tool, BannerClick, to automatically detect,
accept, and reject cookie banners with an accuracy of 99%, 97%, and 87%,
respectively. We find banners to be 56% more prevalent when visiting websites
from within the EU region. Moreover, we analyze the effect of banner
interaction on different types of cookies (i.e., first-party, third-party, and
tracking). For instance, we observe that websites send, on average, 5.5x more
third-party cookies after clicking ``accept'', underlining that it is critical
to interact with banners when performing Web measurements. Additionally, we
analyze statistical consistency, evaluate the widespread deployment of consent
management platforms, compare landing to inner pages, and assess the impact of
visiting a website on a desktop compared to a mobile phone. Our study
highlights that all of these factors substantially impact the cookie landscape,
and thus a multi-perspective approach should be taken when performing Web
measurement studies.
