DOC Add SearchableDropdownField to 5.2.0 changelog

en/04_Changelogs/5.2.0.md

@@ -11,6 +11,7 @@ title: 5.2.0 (unreleased)
   - [ErrorPage allowed codes configuration](#errorpage-allowed-codes-configuration)
   - [Create random passwords for new users](#create-random-passwords-for-new-users)
   - [Buttons to select all files and deselect all files](#bulk-action-buttons)
+  - [SearchableDropdownField components](#searchable-dropdown-field)
   - [More nuanced permissions for `/dev/*` routes](#dev-route-permissions)
   - [Other new features](#other-new-features)
 - [API changes](#api-changes)
@@ -104,6 +105,12 @@ The files section of the CMS now has buttons to select and deselect all files an
 
 ![](../_images/asset-admin-select-all.png)
 
+### SearchableDropdownField components {#searchable-dropdown-field}
+
+A pair of new dropdown react components have been added which are particularly useful for dropdowns with a large number of options. [`SearchableDropdownField`](api:SilverStripe\Forms\SearchableDropdownField) is similar to [`DropdownField`](api:SilverStripe\Forms\DropdownField) which allows selecting a single option, and [`SearchableMultiDropdownField`](api:SilverStripe\Forms\SearchableMultiDropdownField) is similar to [`ListboxField`](api:SilverStripe\Forms\ListboxField) which allows selecting multiple options. Both of these fields include a `setIsLazyLoaded()` method which will load a limited number of options at a time using an AJAX request matching what a user has typed in.
+
+Note that as these are both react components, they are only intended to be used within the CMS.
+
 ### More nuanced permissions for `/dev/*` routes {#dev-route-permissions}
 
 Previously, all `/dev/*` routes registered with [`DevelopmentAdmin`](api:SilverStripe\Dev\DevelopmentAdmin) (for example `/dev/tasks/MyBuildTask`) could only be access by administrator users, and this couldn't be configured.