Your ISP could be MitM-ing your plaintext HTTP already, and it's the use cases that we currently use plaintext HTTP for that this is addressing. If you care ab

Your ISP could be MitM-ing your plaintext HTTP already, and it's the use cases that we currently use plaintext HTTP for that this is addressing. If you care about security of your data, end-to-end, then you should probably only use this feature, if at all, with the proxy running on a machine you control - but presumably in that case you currently aren't using plaintext HTTP for anything anyway, so I don't see how it relates.