onesignal.comは安全ですか？

Used to shame you into surrendering your privacy. By which I mean, it is used to shame you to turn off an ad blocker or any kind of privacy protection. I block this site at my router. I fired off an email to them explaining how my privacy and security are non-negotiable. (Malvertising exists because advertisers allow javascript and other tracking; get rid of javascript in ads and you cannot be scammed that way.) I also explained to them that the internet once existed when privacy was the standard. Thus, if it worked once, it can work again. This website is a privacy risk and unethical.

Light green for me. Seems to be a benign service that helps developers to integrate push notifications in apps. They do quite some tracking with pixels, cookies, etcetera however and share that information with third parties. They are open about this and have a clearly written privacy policy. It is possible to opt-out of some if not all the tracking.