Custom node: comms between html and js files

[GogoVega]

Yes, see

Updating node config on deploy

A common method is to do it in two steps: user adds the node, configures static configs and deploys. user reopens the node to configure all the new dynamically added configs. What matters here is the redeployment because without it you can't save new configs to NR. If this method doesn't suit you, the only other solution is to use the Storage API to save your stuff but since it's not very used there aren't many examples.