fields.flat is not a function

JavaScript
//node_modules/discord.js/src/structures/MessageEmbed.js
static normalizeFields(...fields) {
    return fields
      .reduce((acc, val) => acc.concat(val), [])
      .map(field =>
        this.normalizeField(
          field && field.name,
          field && field.value,
          field && typeof field.inline === 'boolean' ? field.inline : false,
        ),
      );
  }Re-Install Node.js because Discord.js Embeds only work on node version 12 and upupdate node.js// Patched into :
static normalizeFields(...fields) {
    return fields
      .reduce((acc, val) => acc.concat(val), [])
      .map(field =>
        this.normalizeField(
          field && field.name,
          field && field.value,
          field && typeof field.inline === 'boolean' ? field.inline : false,
        ),
      );
  }
Source

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