Leafletjs was the only oss frontend option back in 2015-2016 when we ditched Esri and created our own in-house app, based on Electron. Apart from Mapbox, which was freemium.
It's been around for a long time and is really powerful when compared to other open source web-based mapping/GIS options - unfortunately I never really need the advanced features in the projects I tend to work on.
It's been around for a long time and is really powerful when compared to other open source web-based mapping/GIS options - unfortunately I never really need the advanced features in the projects I tend to work on.
https://openlayers.org/
Edit, my favourite from their list of examples: https://openlayers.org/en/latest/examples/sea-level.html