Warnings at the text format edit page when filter is disabled

Problem/Motivation

Install v3.0.1 of this module on a fresh Drupal 10.3.6 site with composer and enable it. Follow the provided help:

Enable the text format filter Display responsive images or Display image styles and select the images styles/responsive styles that you want to be available to the user.
Create new content. In the editor, click on the image icon in the toolbar. A popup will open where the user can upload an image then assign an image style or responsive style by selecting style from a dropdown menu.

On step 1, as soon as you visit any of the default text formats' edit pages, you get 3 warnings (last one is repeated twice):

1. Warning: Undefined array key "image_styles" in Drupal\inline_responsive_images\Plugin\Filter\FilterImageStyle->settingsForm() (line 115 of modules/contrib/inline_responsive_images/src/Plugin/Filter/FilterImageStyle.php).
2. Warning: Undefined array key "image_styles" in Drupal\inline_responsive_images\Plugin\Filter\FilterResponsiveImageStyle->settingsForm() (line 103 of modules/contrib/inline_responsive_images/src/Plugin/Filter/FilterResponsiveImageStyle.php).
3. Warning: foreach() argument must be of type array|object, null given in Drupal\Core\Render\Element\Checkboxes::valueCallback() (line 113 of core/lib/Drupal/Core/Render/Element/Checkboxes.php).

Those go away after you actually enable the image style filter, but this represents a problem for the text formats that won't enable the filter (eg. Plain text): they will always display the error to the Admin / Site builder.