IndexedDB API

Is there potential to use this? Would be much better I think that existing solutions (i.e. like Leaflet outputting GeoJSON directly to HTML).

sf data can be converted to in-memory vector tiles, saved to the IndexedDB with the key being the MaplibreGL source ID, and a custom protocol for maplibregl could be used to access the data. It looks like there's an upper limit of 2GB per domain, or 50% of the user's free disk space globally.

A Web Worker could be used to convert the sf data to Vector tiles so that it is non-blocking -- or maybe this should be done in R and passed to JS, not sure which is faster.

Currently the vector tiles embedding implementation creates a <img> element in the HTML file, but the raw GeoJSON data is stilled stored in the HTMLWidgets JSON tag.

One way to alleviate this is to encode and compress the GeoJSON before transit to JS. This would require adding some dependencies (like a msgpack encoder, or another binary encoding library, i.e. CBOR), as well as C++ requirements (to keep it fast enough for large spatial data). This would also reduce the HTML file size, since there isn't duplicate data embedded.

Another option it to forgo embedding, and only work with the GeoJSON -- however, this is not optimal 😬.

The best outcome would be to remove the data from the JSON tag, but I'm not currently familiar with how this would be done...