It should be possible to plot a geojson taken from TTNMApper into the NOdeRed plot. As it is not possible to send events from the map the TTN URL could be replaced by some kind of API call to NodeRed telling which radar te plot for 10 seconds.
Showing the geoJSON overlay from https://ttnmapper.org/geojson//radar.geojson works nicely. Removing the overlay by sending msg.payload.command.clear = "layername"; however fails. Need to isolate this.
It should be possible to plot a geojson taken from TTNMApper into the NOdeRed plot. As it is not possible to send events from the map the TTN URL could be replaced by some kind of API call to NodeRed telling which radar te plot for 10 seconds.