I dont think this would be possible if my understanding of how the chromecast works is correct. Once you cast things like youtube, the job of recieving the content is left to the chromecast, so youd need an app that would remove ads then cast that. Otherwise the only thing i could think of is if you made some kind of ad blocking proxy like what DD-WRT does and run your chromecast through that, quitr certain that needs a rooted chromecast though. Of course, an even better solution would be, at least in youtube's case, for google to fix the implementation of ads, at present the skip ad button is shown onthe tv screen, so you are forced to watch the sometimes 5 minute long ads. I may be completely incorrect in saying this, as i said, this is just from my understanding.
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