code: function envelopeIsEqual(env1, env2) {
    const envX1 = env1.geometry.coordinates.map(c => c[0]),
      envY1 = env1.geometry.coordinates.map(c => c[1]),
      envX2 = env2.geometry.coordinates.map(c => c[0]),
      envY2 = env2.geometry.coordinates.map(c => c[1]);
  
    return Math.max(null, envX1) === Math.max(null, envX2) &&
      Math.max(null, envY1) === Math.max(null, envY2) &&
      Math.min(null, envX1) === Math.min(null, envX2) &&
      Math.min(null, envY1) === Math.min(null, envY2);
  }
docs: Checks if two envelopes are equal.
  The function assumes that the arguments are envelopes, i.e.: Rectangular polygon
  
  @param {Feature<Polygon>} env1 - Envelope
  @param {Feature<Polygon>} env2 - Envelope
  @returns {Boolean} - True if the envelopes are equal