toJSON() does not use json_name

[redstubble]

protobuf.js version: "protobufjs": "^6.8.8",

decode message to JSON should use json_name as key.

pbjs -t json-module ...

Generates the following

fields: {
              timestamp: {
                type: "uint64",
                id: 1,
                options: {
                  json_name: "t"
                }
              },
              latitude: {
                type: "double",
                id: 2,
                options: {
                  json_name: "lat"
                }
              },
              longitude: {
                type: "double",
                id: 3,
                options: {
                  json_name: "lon"
                }
              },
              altitude: {
                type: "double",
                id: 4,
                options: {
                  json_name: "alt"
                }
              },
              fields: {
                type: "uint32",
                id: 15,
                options: {
                  json_name: "f"
                }
              }
            }

However whenever I call toJSON() on a message that has been decoded I get strings that are not json_name values. I cannot find any options to create the object with keys reflecting these json_names.

  const test = root.lookupType("com.<>.<>");
  const bin = readBinaryFile("./<>.bin");
  const mess = test.decodeDelimited(bin);
  console.log(mess.toJSON)

Logs

{
  "timestamp": "1557957939176",
  "latitude": 32.305504145820564,
  "longitude": -64.8585479141154,
  "altitude": 65.5
}