Move closer to the original vision of supporting any address-querying implementation desired. Current options include ElectrumX (as before) and now blockchain.com and blockcypher.com since they were easy to support and are publicly/easily available (though ridiculously neither is yet to support bc1 addresses).
- new env var option BTCEXP_ADDRESS_API, value can be electrumx, blockchain.com, blockcypher.com
- update ElectrumX client connect to request v1.4 of API as all clients are now supposed to do
- misc frontend improvements/cleanup for addresses
Dan Janosik