Well, I watch Twitch using a personal fork of https://github.com/SebastianRask/Pocket-Plays-for-Twitch (which isn't really actively maintained), so when Twitch ads became in-stream this year, I replaced the default Android media player it uses with Google's ExoPlayer, and then made a bunch of changes to ExoPlayer to be able to detect when SCTE35 segments would be played, and silenced them.
I modeled my change on similar changes made by Streamlink's Twitch plugin recently: https://github.com/streamlink/streamlink/pull/2372