Do you remember the way the configuration forms work in Drupal 7? No need to create a submit method to store your variables, so if you miss this in Drupal 8 this module is for you my lazy friend.

Using the module

<?php

namespace Drupal\mymodule\Form;

use Drupal\Core\Form\FormStateInterface;
use Drupal\lazy_config_form\Form\LazyConfigForm;

/**
 * Class AdminSettings.
 */
class AdminSettings extends LazyConfigForm {

  /**
   * {@inheritdoc}
   */
  protected function getEditableConfigNames() {
    return [
      'admin.settings',
    ];
  }

  /**
   * {@inheritdoc}
   */
  public function getFormId() {
    return 'admin_settings';
  }

  /**
   * {@inheritdoc}
   */
  public function buildForm(array $form, FormStateInterface $form_state) {
    $config = $this->config($this->getEditableConfigNames()[0]);
    $form['personal_access_token'] = [
      '#type' => 'textfield',
      '#title' => $this->t('Personal Access Token'),
      '#default_value' => $config->get('personal_access_token'),
    ];
    return parent::buildForm($form, $form_state);
  }

}

Issues

As with all contributed modules, when considering submitting an issue:

Read the documentation (two or three times is better). Don't forget the home page.
Review the existing issues list. (Don't forget to select "<- Any ->" for the "Status" field.)
Gather all the appropriate information. This may include (but is not limited to):
- Drupal version.
- Browser type and version.
- Database type and version.
- Error messages, if any.
- Module settings.
Submit the issue. If other modules are involved, you may need to submit the issue to those modules as well.
If you go to provide a patch use the following naming convention:
[lazy_config_form]-[short-description]-[issue-number]-[comment-number]-[drupal-version].patch

And please to report an issue, if you need help to understand how the issue queue works, .

Development version status

The development versions (-dev) are where the newest stuff is, including any bug fixes and new features. We try to make sure it is tested before we commit anything, but occasionally a bug will get from us. Your help on testing this code is greatly appreciated. The translation templates may not always be up-to-date in the dev releases.

RTBC issues for Lazy Config Form

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