[Drupal] Change CKEditor behaviour for line breaks (br or p)

Here is a little code snippet to be added in a .module file.

/**
 * Implements hook_editor_js_settings_alter().
 *
 * {@inheritdoc}
 */
function MODULE_editor_js_settings_alter(array &$settings) {
  foreach ($settings['editor']['formats'] as $name => $value) {
    // Use 
 instead of 
 on enter.
    // See: https://docs.ckeditor.com/ckeditor4/latest/api/CKEDITOR.html#property-ENTER_BR.
    // CKEditor natively converts double 
 into 
 on rendering.
    $settings['editor']['formats'][$name]['editorSettings']['enterMode'] = '2';
  }
}

Additional Information

• Instructions made on Drupal 8.5.x.
• Will break text align buttons in the CKEditor toolbar: Issue on Drupal.org
• The default behaviour of CKEditor is the following:
  • Enter: inserts a paragraph directly in the WYSIWYG,
  • Shift + Enter: inserts a line break.
• The new behaviour of CKEditor with the hook will be:
  • Enter: inserts a single line break (br),
  • 2 × Enter: inserts two line breaks which will be converted into a paragraph when rendered.