I am sure that those looking for a Scrivener replacement, much prefer an native app, and not a browser-based app. However, there are some really interesting browser-based writing apps. The two that I find most interesting are NovelPad and Speare. If you can stomach keeping your work online (and even I'm not too thrilled by that), they may be worth checking out:

https://www.speare.com/

https://novelpad.co/

I wish either of those would make a native Mac app.

Steve Z.