The following features deprecated in Wagtail 3.0 have been fully removed. See [Wagtail 3.0 release notes](/releases/3.0) for details on these changes, including how to remove usage of these features:
* The modules `wagtail.core`, `wagtail.tests`, `wagtail.admin.edit_handlers` and `wagtail.contrib.forms.edit_handlers` are removed.
* The field panel classes `StreamFieldPanel`, `RichTextFieldPanel`, `ImageChooserPanel`, `DocumentChooserPanel` and `SnippetChooserPanel` are removed.
* The `ModelAdmin.get_form_fields_exclude` method is no longer passed a `request` argument.
* The `ModelAdmin.get_edit_handler` method is no longer passed a `request` or `instance` argument.
* The `widget_overrides`, `required_fields`, `required_formsets`, `bind_to`, `render_as_object` and `render_as_field` methods on `Panel` (previously `EditHandler`) are removed.
The following features deprecated in Wagtail 4.0 have been fully removed. See [Wagtail 4.0 release notes](/releases/4.0) for details on these changes, including how to remove usage of these features:
* The `wagtail.contrib.settings.models.BaseSetting` class is removed.
* The `Page.get_latest_revision_as_page` method is removed.
* The `page` and `page_id` properties and `as_page_object` method on `Revision` are removed.
* The JavaScript functions `createPageChooser`, `createSnippetChooser`, `createDocumentChooser` and `createImageChooser` are removed.
* The `wagtail.contrib.modeladmin.menus.SubMenu` class is removed.
* Subclasses of `wagtail.contrib.modeladmin.helpers.AdminURLHelper` are now required to accept a `base_url_path` keyword argument on the constructor.
* The `wagtail.admin.widgets.chooser.AdminChooser` class is removed.
* The `wagtail.snippets.views.snippets.get_snippet_edit_handler` function is removed.
The undocumented `Page.get_static_site_paths` method (which returns a generator of URL paths for use by static site generator packages) has been removed. Packages relying on this functionality should provide their own fallback implementation.
### Progress button (`button-longrunning`) now implemented with Stimulus
The `button-longrunning` class usage has been updated to use the newly adopted Stimulus approach, the previous data attributes will be deprecated in a future release.
If using the old approach, ensure any HTML templates are updated to the new approach before the next major release.
### Old syntax
```html+django
<buttontype="submit"class="button action-save button-longrunning"data-clicked-text="{% trans 'Creating…' %}">
{% icon name="spinner" %}
<em>{% trans 'Create' %}</em>
</button>
```
### New syntax
Minimum required attributes are `data-controller` and a `data-action`.
```html+django
<buttontype="submit"class="button action-save button-longrunning"data-controller="w-progress"data-action="w-progress#activate"data-w-progress-active-value="{% trans 'Creating…' %}">
{% icon name="spinner" %}
<emdata-w-progress-target="label">{% trans 'Create' %}</em>
</button>
```
### Examples of additional capabilities
Stimulus [targets](https://stimulus.hotwired.dev/reference/targets) and [actions](https://stimulus.hotwired.dev/reference/actions) can be leveraged to revise the behaviour via data attributes.
*`<button ... data-w-progress-duration-value="500" ...>` - custom duration can be declared on the element
*`<button ... class="custom-button" data-w-progress-active-class="custom-button--busy" ...>` - custom 'active' class to replace the default `button-longrunning-active` (must be a single string without spaces)
*`<button ... ><strong data-w-progress-target="label">{% trans 'Create' %}</strong></button>` - any element can be the button label (not just `em`)
*`<button ... data-action="w-progress#activate focus->w-progress#activate" ...>` - any event can be used to trigger the in progress behaviour
*`<button ... data-action="w-progress#activate:once" ...>` - only trigger the progress behaviour once
*`<button ... data-action="readystatechange@document->w-progress#activate:once" data-w-progress-duration-value="5000" disabled ...>` - disabled on load (once JS starts) and becomes enabled after 5s duration
