Why is my javascript settings variable empty in Chrome/Edge, but it works in Firefox?

My javascript file starts like this...

var my_global_var;

(function ($, Drupal, drupalSettings) {
  'use strict';

  Drupal.behaviors.myBehavior= {
    'attach': function attach(context, settings) {

      console.log(settings); // settings is empty in Chrome and Edge, but it works in Firefox.

...
    
})

(jQuery, Drupal, drupalSettings);

I add the settings in my block's build method...

  /**
   * {@inheritdoc}
   */
  public function build() {

    $states_select = $this->formBuilder->getForm('Drupal\ed_contact\Form\StatesSelect');

    $states_path = '/state_contacts/';

    return [
      '#theme' => 'ed_contact_info',
      '#attached' => [
        'library' => [
          'ed_contact/ed-contact-us',
          'ed_contact/ed-contact-us-map',
        ],
        'drupalSettings' => [
          'ed_contact' => [
            'states_path' => $states_path,
          ]
        ]
      ],
      '#states_path' => $states_path,
      '#states_select' => $states_select,
      'content' => [
        '#cache' => [
          'contexts' => [
            'url.path',
          ],
        ],
      ],
    ];

  }

Libraries file:

ed-contact-us:
  version: 1.x
  js:
    js/ed-contact-us.js: {}
  dependencies:
    - core/jquery
    - core/drupalSettings

ed-contact-us-map:
  js:
    js/map-config.js: {}
    js/map-interact.js: {}
  dependencies:
    - core/jquery
    - core/drupalSettings

Why might settings be empty in Chrome and Edge? An object is logged to the console, but is empty. In Firefox, settings is populated as expected. I'm following the documentation at https://www.drupal.org/docs/develop/theming-drupal/adding-assets-css-js-to-a-drupal-theme-via-librariesyml#the_process