I don’t know when this started but I noticed it for the first time a few months ago. Some podcasts will have preroll ads that are obviously tailored to me since they are not in the same language as the podcast, instead they are in my native language and if I connect to a VPN in another country the ad will change to one from that country. They also seem to appear regardless of podcast app. I have used both AntennaPod and Spotify. AntennaPod is free so I guess they source their podcasts from some third party website that could be adding in the ads. But since I am paying for Spotify I am expecting not to have to listen to any ads. So who is adding in these ads? Can I get rid of them or am I just stuck with them?
video controls change when an ad is playing on YT, which would be a pretty reliable indicator for an extension running at the client side. But that’s more a UBO issue than sponsorblock when it comes to YouTube, as I’m not sure sponsorblock could do anything if the controls are frozen.