https://MapComplete.org is made by someone from Belgium with the aim of making a website that's at least as good as a native app could be. It's both a data viewer and editor but generally that sounds like it's what you're looking for!

I have yet to get into it myself (I already have established workflows in StreetComplete and other editors) but from the demo that the author gave on CCC ~1.5 years ago it seemed perfectly usable back then already