diff --git a/com.woltlab.wcf/acpSearchProvider.xml b/com.woltlab.wcf/acpSearchProvider.xml
deleted file mode 100644
index f561e00eeb0..00000000000
--- a/com.woltlab.wcf/acpSearchProvider.xml
+++ /dev/null
@@ -1,41 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<data xmlns="http://www.woltlab.com" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.woltlab.com http://www.woltlab.com/XSD/6.0/acpSearchProvider.xsd">
-	<import>
-		<acpsearchprovider name="com.woltlab.wcf.menuItem">
-			<classname>wcf\system\search\acp\MenuItemACPSearchResultProvider</classname>
-			<showorder>1</showorder>
-		</acpsearchprovider>
-		<acpsearchprovider name="com.woltlab.wcf.option">
-			<classname>wcf\system\search\acp\OptionACPSearchResultProvider</classname>
-			<showorder>2</showorder>
-		</acpsearchprovider>
-		<acpsearchprovider name="com.woltlab.wcf.user">
-			<classname>wcf\system\search\acp\UserACPSearchResultProvider</classname>
-			<showorder>3</showorder>
-		</acpsearchprovider>
-		<acpsearchprovider name="com.woltlab.wcf.userGroupOption">
-			<classname>wcf\system\search\acp\UserGroupOptionACPSearchResultProvider</classname>
-			<showorder>4</showorder>
-		</acpsearchprovider>
-		<acpsearchprovider name="com.woltlab.wcf.package">
-			<classname>wcf\system\search\acp\PackageACPSearchResultProvider</classname>
-			<showorder>5</showorder>
-		</acpsearchprovider>
-		<acpsearchprovider name="com.woltlab.wcf.page">
-			<classname>wcf\system\search\acp\PageACPSearchResultProvider</classname>
-			<showorder>6</showorder>
-		</acpsearchprovider>
-		<acpsearchprovider name="com.woltlab.wcf.box">
-			<classname>wcf\system\search\acp\BoxACPSearchResultProvider</classname>
-			<showorder>7</showorder>
-		</acpsearchprovider>
-		<acpsearchprovider name="com.woltlab.wcf.article">
-			<classname>wcf\system\search\acp\ArticleACPSearchResultProvider</classname>
-			<showorder>8</showorder>
-		</acpsearchprovider>
-		<acpsearchprovider name="com.woltlab.wcf.trophy">
-			<classname>wcf\system\search\acp\TrophyACPSearchResultProvider</classname>
-			<showorder>9</showorder>
-		</acpsearchprovider>
-	</import>
-</data>
diff --git a/com.woltlab.wcf/package.xml b/com.woltlab.wcf/package.xml
index 9519e7a6a71..7c9a83c0f28 100644
--- a/com.woltlab.wcf/package.xml
+++ b/com.woltlab.wcf/package.xml
@@ -29,7 +29,6 @@
 		<instruction type="clipboardAction" />
 		<instruction type="objectTypeDefinition" />
 		<instruction type="objectType" />
-		<instruction type="acpSearchProvider" />
 		<instruction type="style">defaultStyle.tar</instruction>
 
 		<instruction type="userOption" run="standalone" />
diff --git a/ts/WoltLabSuite/Core/Acp/Bootstrap.ts b/ts/WoltLabSuite/Core/Acp/Bootstrap.ts
index 9eaa9540a66..b60025f89c1 100644
--- a/ts/WoltLabSuite/Core/Acp/Bootstrap.ts
+++ b/ts/WoltLabSuite/Core/Acp/Bootstrap.ts
@@ -10,6 +10,7 @@ import * as Core from "../Core";
 import { BoostrapOptions, setup as bootstrapSetup } from "../Bootstrap";
 import * as UiPageMenu from "./Ui/Page/Menu";
 import AcpUiPageMenuMainBackend from "./Ui/Page/Menu/Main/Backend";
+import { setup as setupAcpSearch } from "./Ui/Search";
 
 interface AcpBootstrapOptions {
   bootstrap: BoostrapOptions;
@@ -33,4 +34,5 @@ export function setup(options: AcpBootstrapOptions): void {
 
   bootstrapSetup(options.bootstrap);
   UiPageMenu.init();
+  setupAcpSearch();
 }
diff --git a/ts/WoltLabSuite/Core/Acp/Ui/Search.ts b/ts/WoltLabSuite/Core/Acp/Ui/Search.ts
new file mode 100644
index 00000000000..6dc2b6b0c2c
--- /dev/null
+++ b/ts/WoltLabSuite/Core/Acp/Ui/Search.ts
@@ -0,0 +1,337 @@
+/**
+ * Provides the search dropdown for the ACP.
+ *
+ * @author Marcel Werk
+ * @copyright 2001-2026 WoltLab GmbH
+ * @license GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ * @since 6.3
+ * @woltlabExcludeBundle tiny
+ */
+
+import { getPhrase } from "WoltLabSuite/Core/Language";
+import { searchAcp, type AcpSearchResultGroup } from "WoltLabSuite/Core/Api/Acp/Search";
+import UiDropdownSimple from "WoltLabSuite/Core/Ui/Dropdown/Simple";
+
+const DELAY = 250;
+const TRIGGER_LENGTH = 3;
+
+let providerName = "";
+let lastQuery = "";
+let timer: number | undefined;
+let requestToken = 0;
+let itemIndex = -1;
+let navigationItems: HTMLAnchorElement[] = [];
+
+function getSearchContainer(): HTMLElement | null {
+  return document.getElementById("pageHeaderSearch");
+}
+
+function getSearchInput(): HTMLInputElement | null {
+  return document.getElementById("pageHeaderSearchInput") as HTMLInputElement | null;
+}
+
+function getOrCreateList(input: HTMLInputElement): HTMLUListElement {
+  let list = input.parentElement!.querySelector<HTMLUListElement>(".acpSearchDropdown");
+  if (list === null) {
+    list = document.createElement("ul");
+    list.className = "dropdownMenu acpSearchDropdown";
+    list.dataset.dropdownIgnorePageScroll = "true";
+    input.insertAdjacentElement("afterend", list);
+  }
+
+  return list;
+}
+
+function showList(list: HTMLUListElement): void {
+  const container = document.querySelector<HTMLElement>("#pageHeaderSearch .pageHeaderSearchInputContainer");
+  if (container !== null) {
+    const { bottom } = container.getBoundingClientRect();
+    list.style.setProperty("top", `${Math.trunc(bottom)}px`, "important");
+  }
+
+  list.classList.add("dropdownOpen");
+}
+
+function clearList(list: HTMLUListElement): void {
+  list.innerHTML = "";
+  list.classList.remove("dropdownOpen");
+  navigationItems = [];
+  itemIndex = -1;
+}
+
+function renderEmpty(list: HTMLUListElement): void {
+  clearList(list);
+
+  const empty = document.createElement("li");
+  empty.className = "dropdownText";
+  empty.textContent = getPhrase("wcf.acp.search.noResults");
+  list.append(empty);
+
+  showList(list);
+}
+
+function renderResults(list: HTMLUListElement, groups: AcpSearchResultGroup[]): void {
+  clearList(list);
+
+  if (groups.length === 0) {
+    renderEmpty(list);
+    return;
+  }
+
+  groups.forEach((group, index) => {
+    if (index > 0) {
+      const divider = document.createElement("li");
+      divider.className = "dropdownDivider";
+      list.append(divider);
+    }
+
+    const caption = document.createElement("li");
+    caption.className = "dropdownText";
+    caption.textContent = group.title;
+    list.append(caption);
+
+    for (const item of group.items) {
+      const li = document.createElement("li");
+      const link = document.createElement("a");
+      link.href = item.link;
+
+      const title = document.createElement("span");
+      title.textContent = item.title;
+      link.append(title);
+
+      if (item.subtitle) {
+        const subtitle = document.createElement("small");
+        subtitle.textContent = item.subtitle;
+        link.append(subtitle);
+      }
+
+      li.append(link);
+      list.append(li);
+      navigationItems.push(link);
+    }
+  });
+
+  truncateSubtitles(list);
+  showList(list);
+}
+
+function truncateSubtitles(list: HTMLUListElement): void {
+  list.querySelectorAll<HTMLElement>("small").forEach((element) => {
+    while (element.scrollWidth > element.clientWidth) {
+      element.innerText = `… ${element.innerText.substring(3)}`;
+    }
+  });
+}
+
+function highlightItem(): void {
+  navigationItems.forEach((link, index) => {
+    link.parentElement!.classList.toggle("dropdownNavigationItem", index === itemIndex);
+  });
+}
+
+function selectNext(): void {
+  if (navigationItems.length === 0) {
+    return;
+  }
+
+  itemIndex = (itemIndex + 1) % navigationItems.length;
+  highlightItem();
+}
+
+function selectPrevious(): void {
+  if (navigationItems.length === 0) {
+    return;
+  }
+
+  itemIndex = itemIndex <= 0 ? navigationItems.length - 1 : itemIndex - 1;
+  highlightItem();
+}
+
+function activateSelection(): boolean {
+  if (itemIndex < 0 || itemIndex >= navigationItems.length) {
+    return false;
+  }
+
+  window.location.href = navigationItems[itemIndex].href;
+  return true;
+}
+
+async function performSearch(query: string): Promise<void> {
+  const input = getSearchInput();
+  if (input === null) {
+    return;
+  }
+
+  const token = ++requestToken;
+  const list = getOrCreateList(input);
+
+  const response = await searchAcp(query, providerName);
+  if (token !== requestToken) {
+    return;
+  }
+  if (!response.ok) {
+    return;
+  }
+
+  renderResults(list, response.value.results);
+}
+
+function scheduleSearch(query: string): void {
+  if (timer !== undefined) {
+    window.clearTimeout(timer);
+  }
+
+  timer = window.setTimeout(() => {
+    timer = undefined;
+    void performSearch(query);
+  }, DELAY);
+}
+
+function onInput(event: Event): void {
+  const input = event.currentTarget as HTMLInputElement;
+  const query = input.value.trim();
+
+  if (query.length < TRIGGER_LENGTH) {
+    requestToken++;
+    if (timer !== undefined) {
+      window.clearTimeout(timer);
+      timer = undefined;
+    }
+    lastQuery = "";
+
+    const list = input.parentElement!.querySelector<HTMLUListElement>(".acpSearchDropdown");
+    if (list !== null) {
+      clearList(list);
+    }
+
+    return;
+  }
+
+  if (query === lastQuery) {
+    return;
+  }
+
+  lastQuery = query;
+  scheduleSearch(query);
+}
+
+function onKeyDown(event: KeyboardEvent): void {
+  switch (event.key) {
+    case "ArrowDown":
+      event.preventDefault();
+      selectNext();
+      return;
+    case "ArrowUp":
+      event.preventDefault();
+      selectPrevious();
+      return;
+    case "Enter":
+      if (activateSelection()) {
+        event.preventDefault();
+      }
+      return;
+    case "Escape": {
+      const input = event.currentTarget as HTMLInputElement;
+      if (input.value.trim() === "") {
+        event.preventDefault();
+        input.blur();
+      }
+      return;
+    }
+  }
+}
+
+function onBlur(event: FocusEvent): void {
+  const input = event.currentTarget as HTMLInputElement;
+  // Defer to allow click on result items to register.
+  window.setTimeout(() => {
+    const list = input.parentElement?.querySelector<HTMLUListElement>(".acpSearchDropdown");
+    if (list !== null && list !== undefined) {
+      clearList(list);
+    }
+  }, 250);
+}
+
+function initProviderSelection(): void {
+  // `UiDropdownSimple` reparents the dropdown menu to a global container
+  // during its lazy initialization, so the menu items are no longer
+  // descendants of `#pageHeaderSearchType` at this point. Look it up
+  // through the dropdown registry instead.
+  const menu = UiDropdownSimple.getDropdownMenu("pageHeaderSearchType");
+  if (menu === undefined) {
+    return;
+  }
+
+  menu.addEventListener("click", (event) => {
+    const target = event.target as HTMLElement | null;
+    const link = target?.closest<HTMLAnchorElement>("a[data-provider-name]") ?? null;
+    if (link === null) {
+      return;
+    }
+
+    event.preventDefault();
+
+    const label = document.querySelector<HTMLElement>(
+      ".pageHeaderSearchType > .button > .pageHeaderSearchTypeLabel",
+    );
+    if (label !== null) {
+      label.textContent = link.textContent;
+    }
+
+    const oldProvider = providerName;
+    const newProvider = link.dataset.providerName === "everywhere" ? "" : link.dataset.providerName!;
+    providerName = newProvider;
+
+    if (oldProvider !== newProvider) {
+      const input = getSearchInput();
+      if (input !== null) {
+        const query = input.value.trim();
+        if (query.length >= TRIGGER_LENGTH) {
+          lastQuery = query;
+          void performSearch(query);
+        }
+      }
+    }
+  });
+}
+
+function initShortcuts(input: HTMLInputElement): void {
+  document.addEventListener(
+    "keydown",
+    (event) => {
+      if (event.key !== "s") {
+        return;
+      }
+      if (event.defaultPrevented || document.activeElement !== document.body) {
+        return;
+      }
+
+      event.preventDefault();
+      input.focus();
+    },
+    { passive: false },
+  );
+}
+
+export function setup(): void {
+  const container = getSearchContainer();
+  if (container === null) {
+    return;
+  }
+
+  const input = getSearchInput();
+  if (input === null) {
+    return;
+  }
+
+  const form = container.querySelector("form");
+  form?.addEventListener("submit", (event) => event.preventDefault());
+
+  input.autocomplete = "off";
+  input.addEventListener("input", onInput);
+  input.addEventListener("keydown", onKeyDown);
+  input.addEventListener("blur", onBlur);
+
+  initProviderSelection();
+  initShortcuts(input);
+}
diff --git a/ts/WoltLabSuite/Core/Api/Acp/Search.ts b/ts/WoltLabSuite/Core/Api/Acp/Search.ts
new file mode 100644
index 00000000000..a9038e17e9d
--- /dev/null
+++ b/ts/WoltLabSuite/Core/Api/Acp/Search.ts
@@ -0,0 +1,44 @@
+/**
+ * Fetches ACP search results for a given query.
+ *
+ * @author Marcel Werk
+ * @copyright 2001-2026 WoltLab GmbH
+ * @license GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ * @since 6.3
+ * @woltlabExcludeBundle tiny
+ */
+
+import { prepareRequest } from "WoltLabSuite/Core/Ajax/Backend";
+import { ApiResult, apiResultFromError, apiResultFromValue } from "WoltLabSuite/Core/Api/Result";
+
+export type AcpSearchResultItem = {
+  link: string;
+  title: string;
+  subtitle?: string;
+};
+
+export type AcpSearchResultGroup = {
+  title: string;
+  items: AcpSearchResultItem[];
+};
+
+type Response = {
+  results: AcpSearchResultGroup[];
+};
+
+export async function searchAcp(query: string, provider = ""): Promise<ApiResult<Response>> {
+  const url = new URL(`${window.WSC_RPC_API_URL}core/acp/search`);
+  url.searchParams.set("query", query);
+  if (provider) {
+    url.searchParams.set("provider", provider);
+  }
+
+  let response: Response;
+  try {
+    response = (await prepareRequest(url.toString()).get().fetchAsJson()) as Response;
+  } catch (e) {
+    return apiResultFromError(e);
+  }
+
+  return apiResultFromValue(response);
+}
diff --git a/wcfsetup/install/files/acp/js/WCF.ACP.js b/wcfsetup/install/files/acp/js/WCF.ACP.js
index 65fc3e22fe5..af81cf86d28 100644
--- a/wcfsetup/install/files/acp/js/WCF.ACP.js
+++ b/wcfsetup/install/files/acp/js/WCF.ACP.js
@@ -807,166 +807,6 @@ WCF.ACP.Worker = Class.extend({
 	}
 });
 
-/**
- * Provides the search dropdown for ACP
- * 
- * @see	WCF.Search.Base
- */
-WCF.ACP.Search = WCF.Search.Base.extend({
-	_delay: 250,
-	
-	/**
-	 * name of the selected search provider
-	 * @var	string
-	 */
-	_providerName: '',
-	
-	/**
-	 * @see	WCF.Search.Base.init()
-	 */
-	init: function() {
-		this._className = 'wcf\\data\\acp\\search\\provider\\ACPSearchProviderAction';
-		this._super('#pageHeaderSearch input[name=q]');
-		
-		// disable form submitting
-		$('#pageHeaderSearch > form').on('submit', function(event) {
-			event.preventDefault();
-		});
-		
-		var $dropdown = WCF.Dropdown.getDropdownMenu('pageHeaderSearchType');
-		$dropdown.find('a[data-provider-name]').on('click', $.proxy(function(event) {
-			event.preventDefault();
-			var $button = $(event.target);
-			$('.pageHeaderSearchType > .button > .pageHeaderSearchTypeLabel').text($button.text());
-			
-			var $oldProviderName = this._providerName;
-			this._providerName = ($button.data('providerName') != 'everywhere' ? $button.data('providerName') : '');
-			
-			if ($oldProviderName != this._providerName) {
-				var $searchString = $.trim(this._searchInput.val());
-				if ($searchString) {
-					var $parameters = {
-						data: {
-							excludedSearchValues: this._excludedSearchValues,
-							searchString: $searchString
-						}
-					};
-					this._queryServer($parameters);
-				}
-			}
-		}, this));
-
-		const searchInput = document.querySelector("#pageHeaderSearch input[name=q]");
-		document.addEventListener("keydown", (event) => {
-			if (event.key !== "s") {
-				return;
-			}
-			
-			if (!event.defaultPrevented && document.activeElement === document.body) {
-				searchInput.focus();
-
-				event.preventDefault();
-			}
-		}, {
-			passive: false,
-		});
-
-		searchInput.addEventListener("keydown", (event) => {
-			if (event.key !== "Escape") {
-				return;
-			}
-
-			if (!event.defaultPrevented && searchInput.value.trim() === "") {
-				event.preventDefault();
-
-				searchInput.blur();
-			}
-		}, {
-			passive: false,
-		});
-	},
-	
-	/**
-	 * @see	WCF.Search.Base._createListItem()
-	 */
-	_createListItem: function(resultList) {
-		// add a divider between result lists
-		if (this._list.children('li').length > 0) {
-			$('<li class="dropdownDivider" />').appendTo(this._list);
-		}
-		
-		// add caption
-		$('<li class="dropdownText">' + resultList.title + '</li>').appendTo(this._list);
-		
-		// add menu items
-		for (var $i in resultList.items) {
-			var $item = resultList.items[$i];
-			
-			$('<li><a href="' + $item.link + '"><span>' + WCF.String.escapeHTML($item.title) + '</span>' + ($item.subtitle ? '<small>' + WCF.String.escapeHTML($item.subtitle) + '</small>' : '') + '</a></li>').appendTo(this._list);
-			
-			this._itemCount++;
-		}
-	},
-	
-	/**
-	 * @see	WCF.Search.Base._openDropdown()
-	 */
-	_openDropdown: function() {
-		this._list.find('small').each(function(index, element) {
-			while (element.scrollWidth > element.clientWidth) {
-				element.innerText = '\u2026 ' + element.innerText.substr(3);
-			}
-		});
-	},
-	
-	/**
-	 * @see	WCF.Search.Base._handleEmptyResult()
-	 */
-	_handleEmptyResult: function() {
-		$('<li class="dropdownText">' + WCF.Language.get('wcf.acp.search.noResults') + '</li>').appendTo(this._list);
-		
-		return true;
-	},
-	
-	/**
-	 * @see	WCF.Search.Base._highlightSelectedElement()
-	 */
-	_highlightSelectedElement: function() {
-		this._list.find('li').removeClass('dropdownNavigationItem');
-		this._list.find('li:not(.dropdownDivider):not(.dropdownText)').eq(this._itemIndex).addClass('dropdownNavigationItem');
-	},
-	
-	/**
-	 * @see	WCF.Search.Base._selectElement()
-	 */
-	_selectElement: function(event) {
-		if (this._itemIndex === -1) {
-			return false;
-		}
-		
-		window.location = this._list.find('li.dropdownNavigationItem > a').attr('href');
-	},
-	
-	_success: function(data) {
-		this._super(data);
-		
-		const container = document.getElementById("pageHeaderSearch").querySelector(".pageHeaderSearchInputContainer");
-		const { bottom } = container.getBoundingClientRect();
-		this._list[0].style.setProperty("top", `${Math.trunc(bottom)}px`, "important");
-		this._list[0].classList.add("acpSearchDropdown");
-		this._list[0].dataset.dropdownIgnorePageScroll = "true";
-	},
-	
-	/**
-	 * @see	WCF.Search.Base._getParameters()
-	 */
-	_getParameters: function(parameters) {
-		parameters.data.providerName = this._providerName;
-		
-		return parameters;
-	}
-});
-
 /**
  * Namespace for stat-related classes.
  */
diff --git a/wcfsetup/install/files/acp/templates/header.tpl b/wcfsetup/install/files/acp/templates/header.tpl
index 250ba7c5eb5..7ce3667ab11 100644
--- a/wcfsetup/install/files/acp/templates/header.tpl
+++ b/wcfsetup/install/files/acp/templates/header.tpl
@@ -135,11 +135,7 @@
 	<script>
 		$(function() {
 			if (jQuery.browser.touch) $('html').addClass('touch');
-			
-			{if $__wcf->user->userID && $__isLogin|empty}
-				new WCF.ACP.Search();
-			{/if}
-			
+
 			{event name='javascriptInit'}
 			
 			$('form[method=get]').attr('method', 'post');
diff --git a/wcfsetup/install/files/js/WoltLabSuite/Core/Acp/Bootstrap.js b/wcfsetup/install/files/js/WoltLabSuite/Core/Acp/Bootstrap.js
index 6b12fdef092..0ca607e41e0 100644
--- a/wcfsetup/install/files/js/WoltLabSuite/Core/Acp/Bootstrap.js
+++ b/wcfsetup/install/files/js/WoltLabSuite/Core/Acp/Bootstrap.js
@@ -5,7 +5,7 @@
  * @copyright  2001-2019 WoltLab GmbH
  * @license  GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
  */
-define(["require", "exports", "tslib", "../Core", "../Bootstrap", "./Ui/Page/Menu", "./Ui/Page/Menu/Main/Backend"], function (require, exports, tslib_1, Core, Bootstrap_1, UiPageMenu, Backend_1) {
+define(["require", "exports", "tslib", "../Core", "../Bootstrap", "./Ui/Page/Menu", "./Ui/Page/Menu/Main/Backend", "./Ui/Search"], function (require, exports, tslib_1, Core, Bootstrap_1, UiPageMenu, Backend_1, Search_1) {
     "use strict";
     Object.defineProperty(exports, "__esModule", { value: true });
     exports.setup = setup;
@@ -26,5 +26,6 @@ define(["require", "exports", "tslib", "../Core", "../Bootstrap", "./Ui/Page/Men
         }, options);
         (0, Bootstrap_1.setup)(options.bootstrap);
         UiPageMenu.init();
+        (0, Search_1.setup)();
     }
 });
diff --git a/wcfsetup/install/files/js/WoltLabSuite/Core/Acp/Ui/Search.js b/wcfsetup/install/files/js/WoltLabSuite/Core/Acp/Ui/Search.js
new file mode 100644
index 00000000000..865ec3aacca
--- /dev/null
+++ b/wcfsetup/install/files/js/WoltLabSuite/Core/Acp/Ui/Search.js
@@ -0,0 +1,277 @@
+/**
+ * Provides the search dropdown for the ACP.
+ *
+ * @author Marcel Werk
+ * @copyright 2001-2026 WoltLab GmbH
+ * @license GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ * @since 6.3
+ * @woltlabExcludeBundle tiny
+ */
+define(["require", "exports", "tslib", "WoltLabSuite/Core/Language", "WoltLabSuite/Core/Api/Acp/Search", "WoltLabSuite/Core/Ui/Dropdown/Simple"], function (require, exports, tslib_1, Language_1, Search_1, Simple_1) {
+    "use strict";
+    Object.defineProperty(exports, "__esModule", { value: true });
+    exports.setup = setup;
+    Simple_1 = tslib_1.__importDefault(Simple_1);
+    const DELAY = 250;
+    const TRIGGER_LENGTH = 3;
+    let providerName = "";
+    let lastQuery = "";
+    let timer;
+    let requestToken = 0;
+    let itemIndex = -1;
+    let navigationItems = [];
+    function getSearchContainer() {
+        return document.getElementById("pageHeaderSearch");
+    }
+    function getSearchInput() {
+        return document.getElementById("pageHeaderSearchInput");
+    }
+    function getOrCreateList(input) {
+        let list = input.parentElement.querySelector(".acpSearchDropdown");
+        if (list === null) {
+            list = document.createElement("ul");
+            list.className = "dropdownMenu acpSearchDropdown";
+            list.dataset.dropdownIgnorePageScroll = "true";
+            input.insertAdjacentElement("afterend", list);
+        }
+        return list;
+    }
+    function showList(list) {
+        const container = document.querySelector("#pageHeaderSearch .pageHeaderSearchInputContainer");
+        if (container !== null) {
+            const { bottom } = container.getBoundingClientRect();
+            list.style.setProperty("top", `${Math.trunc(bottom)}px`, "important");
+        }
+        list.classList.add("dropdownOpen");
+    }
+    function clearList(list) {
+        list.innerHTML = "";
+        list.classList.remove("dropdownOpen");
+        navigationItems = [];
+        itemIndex = -1;
+    }
+    function renderEmpty(list) {
+        clearList(list);
+        const empty = document.createElement("li");
+        empty.className = "dropdownText";
+        empty.textContent = (0, Language_1.getPhrase)("wcf.acp.search.noResults");
+        list.append(empty);
+        showList(list);
+    }
+    function renderResults(list, groups) {
+        clearList(list);
+        if (groups.length === 0) {
+            renderEmpty(list);
+            return;
+        }
+        groups.forEach((group, index) => {
+            if (index > 0) {
+                const divider = document.createElement("li");
+                divider.className = "dropdownDivider";
+                list.append(divider);
+            }
+            const caption = document.createElement("li");
+            caption.className = "dropdownText";
+            caption.textContent = group.title;
+            list.append(caption);
+            for (const item of group.items) {
+                const li = document.createElement("li");
+                const link = document.createElement("a");
+                link.href = item.link;
+                const title = document.createElement("span");
+                title.textContent = item.title;
+                link.append(title);
+                if (item.subtitle) {
+                    const subtitle = document.createElement("small");
+                    subtitle.textContent = item.subtitle;
+                    link.append(subtitle);
+                }
+                li.append(link);
+                list.append(li);
+                navigationItems.push(link);
+            }
+        });
+        truncateSubtitles(list);
+        showList(list);
+    }
+    function truncateSubtitles(list) {
+        list.querySelectorAll("small").forEach((element) => {
+            while (element.scrollWidth > element.clientWidth) {
+                element.innerText = `… ${element.innerText.substring(3)}`;
+            }
+        });
+    }
+    function highlightItem() {
+        navigationItems.forEach((link, index) => {
+            link.parentElement.classList.toggle("dropdownNavigationItem", index === itemIndex);
+        });
+    }
+    function selectNext() {
+        if (navigationItems.length === 0) {
+            return;
+        }
+        itemIndex = (itemIndex + 1) % navigationItems.length;
+        highlightItem();
+    }
+    function selectPrevious() {
+        if (navigationItems.length === 0) {
+            return;
+        }
+        itemIndex = itemIndex <= 0 ? navigationItems.length - 1 : itemIndex - 1;
+        highlightItem();
+    }
+    function activateSelection() {
+        if (itemIndex < 0 || itemIndex >= navigationItems.length) {
+            return false;
+        }
+        window.location.href = navigationItems[itemIndex].href;
+        return true;
+    }
+    async function performSearch(query) {
+        const input = getSearchInput();
+        if (input === null) {
+            return;
+        }
+        const token = ++requestToken;
+        const list = getOrCreateList(input);
+        const response = await (0, Search_1.searchAcp)(query, providerName);
+        if (token !== requestToken) {
+            return;
+        }
+        if (!response.ok) {
+            return;
+        }
+        renderResults(list, response.value.results);
+    }
+    function scheduleSearch(query) {
+        if (timer !== undefined) {
+            window.clearTimeout(timer);
+        }
+        timer = window.setTimeout(() => {
+            timer = undefined;
+            void performSearch(query);
+        }, DELAY);
+    }
+    function onInput(event) {
+        const input = event.currentTarget;
+        const query = input.value.trim();
+        if (query.length < TRIGGER_LENGTH) {
+            requestToken++;
+            if (timer !== undefined) {
+                window.clearTimeout(timer);
+                timer = undefined;
+            }
+            lastQuery = "";
+            const list = input.parentElement.querySelector(".acpSearchDropdown");
+            if (list !== null) {
+                clearList(list);
+            }
+            return;
+        }
+        if (query === lastQuery) {
+            return;
+        }
+        lastQuery = query;
+        scheduleSearch(query);
+    }
+    function onKeyDown(event) {
+        switch (event.key) {
+            case "ArrowDown":
+                event.preventDefault();
+                selectNext();
+                return;
+            case "ArrowUp":
+                event.preventDefault();
+                selectPrevious();
+                return;
+            case "Enter":
+                if (activateSelection()) {
+                    event.preventDefault();
+                }
+                return;
+            case "Escape": {
+                const input = event.currentTarget;
+                if (input.value.trim() === "") {
+                    event.preventDefault();
+                    input.blur();
+                }
+                return;
+            }
+        }
+    }
+    function onBlur(event) {
+        const input = event.currentTarget;
+        // Defer to allow click on result items to register.
+        window.setTimeout(() => {
+            const list = input.parentElement?.querySelector(".acpSearchDropdown");
+            if (list !== null && list !== undefined) {
+                clearList(list);
+            }
+        }, 250);
+    }
+    function initProviderSelection() {
+        // `UiDropdownSimple` reparents the dropdown menu to a global container
+        // during its lazy initialization, so the menu items are no longer
+        // descendants of `#pageHeaderSearchType` at this point. Look it up
+        // through the dropdown registry instead.
+        const menu = Simple_1.default.getDropdownMenu("pageHeaderSearchType");
+        if (menu === undefined) {
+            return;
+        }
+        menu.addEventListener("click", (event) => {
+            const target = event.target;
+            const link = target?.closest("a[data-provider-name]") ?? null;
+            if (link === null) {
+                return;
+            }
+            event.preventDefault();
+            const label = document.querySelector(".pageHeaderSearchType > .button > .pageHeaderSearchTypeLabel");
+            if (label !== null) {
+                label.textContent = link.textContent;
+            }
+            const oldProvider = providerName;
+            const newProvider = link.dataset.providerName === "everywhere" ? "" : link.dataset.providerName;
+            providerName = newProvider;
+            if (oldProvider !== newProvider) {
+                const input = getSearchInput();
+                if (input !== null) {
+                    const query = input.value.trim();
+                    if (query.length >= TRIGGER_LENGTH) {
+                        lastQuery = query;
+                        void performSearch(query);
+                    }
+                }
+            }
+        });
+    }
+    function initShortcuts(input) {
+        document.addEventListener("keydown", (event) => {
+            if (event.key !== "s") {
+                return;
+            }
+            if (event.defaultPrevented || document.activeElement !== document.body) {
+                return;
+            }
+            event.preventDefault();
+            input.focus();
+        }, { passive: false });
+    }
+    function setup() {
+        const container = getSearchContainer();
+        if (container === null) {
+            return;
+        }
+        const input = getSearchInput();
+        if (input === null) {
+            return;
+        }
+        const form = container.querySelector("form");
+        form?.addEventListener("submit", (event) => event.preventDefault());
+        input.autocomplete = "off";
+        input.addEventListener("input", onInput);
+        input.addEventListener("keydown", onKeyDown);
+        input.addEventListener("blur", onBlur);
+        initProviderSelection();
+        initShortcuts(input);
+    }
+});
diff --git a/wcfsetup/install/files/js/WoltLabSuite/Core/Api/Acp/Search.js b/wcfsetup/install/files/js/WoltLabSuite/Core/Api/Acp/Search.js
new file mode 100644
index 00000000000..82f655d4957
--- /dev/null
+++ b/wcfsetup/install/files/js/WoltLabSuite/Core/Api/Acp/Search.js
@@ -0,0 +1,29 @@
+/**
+ * Fetches ACP search results for a given query.
+ *
+ * @author Marcel Werk
+ * @copyright 2001-2026 WoltLab GmbH
+ * @license GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ * @since 6.3
+ * @woltlabExcludeBundle tiny
+ */
+define(["require", "exports", "WoltLabSuite/Core/Ajax/Backend", "WoltLabSuite/Core/Api/Result"], function (require, exports, Backend_1, Result_1) {
+    "use strict";
+    Object.defineProperty(exports, "__esModule", { value: true });
+    exports.searchAcp = searchAcp;
+    async function searchAcp(query, provider = "") {
+        const url = new URL(`${window.WSC_RPC_API_URL}core/acp/search`);
+        url.searchParams.set("query", query);
+        if (provider) {
+            url.searchParams.set("provider", provider);
+        }
+        let response;
+        try {
+            response = (await (0, Backend_1.prepareRequest)(url.toString()).get().fetchAsJson());
+        }
+        catch (e) {
+            return (0, Result_1.apiResultFromError)(e);
+        }
+        return (0, Result_1.apiResultFromValue)(response);
+    }
+});
diff --git a/wcfsetup/install/files/lib/bootstrap/com.woltlab.wcf.php b/wcfsetup/install/files/lib/bootstrap/com.woltlab.wcf.php
index caf97c0927e..4efb5e9c5cd 100644
--- a/wcfsetup/install/files/lib/bootstrap/com.woltlab.wcf.php
+++ b/wcfsetup/install/files/lib/bootstrap/com.woltlab.wcf.php
@@ -14,6 +14,7 @@ public function __invoke(): void
     {
         $this->initEventListeners();
         $this->initACPMenuItems();
+        $this->initACPSearchProviders();
         $this->initLicenseData();
     }
 
@@ -135,6 +136,14 @@ private function initACPMenuItems(): void
         );
     }
 
+    private function initACPSearchProviders(): void
+    {
+        EventHandler::getInstance()->register(
+            \wcf\event\acp\search\provider\ProviderCollecting::class,
+            \wcf\system\event\listener\AcpSearchProviderCollectingListener::class
+        );
+    }
+
     private function initLicenseData(): void
     {
         try {
diff --git a/wcfsetup/install/files/lib/data/acp/search/provider/ACPSearchProvider.class.php b/wcfsetup/install/files/lib/data/acp/search/provider/ACPSearchProvider.class.php
index e03f3d5dd25..650cd779f30 100644
--- a/wcfsetup/install/files/lib/data/acp/search/provider/ACPSearchProvider.class.php
+++ b/wcfsetup/install/files/lib/data/acp/search/provider/ACPSearchProvider.class.php
@@ -16,6 +16,8 @@
  * @property-read   string  $providerName   textual identifier of the ACP search provider
  * @property-read   string  $className      class name of the `wcf\system\search\acp\IACPSearchResultProvider` implementation executing the search
  * @property-read   int     $showOrder      position of the grouped results of the ACP search provider within the result list
+ *
+ * @deprecated 6.3 Register providers through the `wcf\event\acp\search\provider\ProviderCollecting` event.
  */
 class ACPSearchProvider extends DatabaseObject
 {
diff --git a/wcfsetup/install/files/lib/data/acp/search/provider/ACPSearchProviderAction.class.php b/wcfsetup/install/files/lib/data/acp/search/provider/ACPSearchProviderAction.class.php
index 6ca35d46669..608963307f5 100644
--- a/wcfsetup/install/files/lib/data/acp/search/provider/ACPSearchProviderAction.class.php
+++ b/wcfsetup/install/files/lib/data/acp/search/provider/ACPSearchProviderAction.class.php
@@ -3,8 +3,6 @@
 namespace wcf\data\acp\search\provider;
 
 use wcf\data\AbstractDatabaseObjectAction;
-use wcf\data\ISearchAction;
-use wcf\system\search\acp\ACPSearchHandler;
 
 /**
  * Executes ACP search provider-related actions.
@@ -14,61 +12,8 @@
  * @license GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
  *
  * @extends AbstractDatabaseObjectAction<ACPSearchProvider, ACPSearchProviderEditor>
+ * @deprecated 6.3 ACP search providers are registered through the
+ *             `wcf\event\acp\search\provider\ProviderCollecting` event. The
+ *             search itself is served by the `/core/acp/search` RPC endpoint.
  */
-class ACPSearchProviderAction extends AbstractDatabaseObjectAction implements ISearchAction
-{
-    /**
-     * @inheritDoc
-     */
-    protected $requireACP = ['getSearchResultList'];
-
-    #[\Override]
-    public function validateGetSearchResultList()
-    {
-        $this->readString('searchString', false, 'data');
-    }
-
-    #[\Override]
-    public function getSearchResultList()
-    {
-        $data = [];
-        $results = ACPSearchHandler::getInstance()->search(
-            $this->parameters['data']['searchString'],
-            20,
-            (!empty($this->parameters['data']['providerName']) ? $this->parameters['data']['providerName'] : '')
-        );
-
-        foreach ($results as $resultList) {
-            $items = [];
-            foreach ($resultList as $item) {
-                $items[] = [
-                    'link' => $item->getLink(),
-                    'subtitle' => $item->getSubtitle(),
-                    'title' => $item->getTitle(),
-                ];
-            }
-
-            foreach ($items as $key => &$item) {
-                $double = false;
-                foreach ($items as $key2 => $item2) {
-                    if ($key != $key2 && !\strcasecmp($item['title'], $item2['title'])) {
-                        $double = true;
-                        break;
-                    }
-                }
-
-                if (!$double) {
-                    unset($item['subtitle']);
-                }
-            }
-            unset($item);
-
-            $data[] = [
-                'items' => $items,
-                'title' => $resultList->getTitle(),
-            ];
-        }
-
-        return $data;
-    }
-}
+class ACPSearchProviderAction extends AbstractDatabaseObjectAction {}
diff --git a/wcfsetup/install/files/lib/data/acp/search/provider/ACPSearchProviderEditor.class.php b/wcfsetup/install/files/lib/data/acp/search/provider/ACPSearchProviderEditor.class.php
index b3bfc08d74e..0a6be1a2711 100644
--- a/wcfsetup/install/files/lib/data/acp/search/provider/ACPSearchProviderEditor.class.php
+++ b/wcfsetup/install/files/lib/data/acp/search/provider/ACPSearchProviderEditor.class.php
@@ -13,6 +13,8 @@
  *
  * @mixin       ACPSearchProvider
  * @extends DatabaseObjectEditor<ACPSearchProvider>
+ *
+ * @deprecated 6.3
  */
 class ACPSearchProviderEditor extends DatabaseObjectEditor
 {
diff --git a/wcfsetup/install/files/lib/data/acp/search/provider/ACPSearchProviderList.class.php b/wcfsetup/install/files/lib/data/acp/search/provider/ACPSearchProviderList.class.php
index e72672cb6e3..20a11bff75b 100644
--- a/wcfsetup/install/files/lib/data/acp/search/provider/ACPSearchProviderList.class.php
+++ b/wcfsetup/install/files/lib/data/acp/search/provider/ACPSearchProviderList.class.php
@@ -12,6 +12,8 @@
  * @license GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
  *
  * @extends DatabaseObjectList<ACPSearchProvider>
+ *
+ * @deprecated 6.3
  */
 class ACPSearchProviderList extends DatabaseObjectList
 {
diff --git a/wcfsetup/install/files/lib/event/acp/search/provider/ProviderCollecting.class.php b/wcfsetup/install/files/lib/event/acp/search/provider/ProviderCollecting.class.php
new file mode 100644
index 00000000000..ee3d37a5e63
--- /dev/null
+++ b/wcfsetup/install/files/lib/event/acp/search/provider/ProviderCollecting.class.php
@@ -0,0 +1,35 @@
+<?php
+
+namespace wcf\event\acp\search\provider;
+
+use wcf\event\IPsr14Event;
+use wcf\system\search\acp\IACPSearchResultProvider;
+
+/**
+ * Requests the collection of acp search providers.
+ *
+ * @author      Marcel Werk
+ * @copyright   2001-2026 WoltLab GmbH
+ * @license     GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ * @since       6.3
+ */
+final class ProviderCollecting implements IPsr14Event
+{
+    /**
+     * @var array<string, IACPSearchResultProvider>
+     */
+    private array $providers = [];
+
+    public function register(string $providerName, IACPSearchResultProvider $provider): void
+    {
+        $this->providers[$providerName] = $provider;
+    }
+
+    /**
+     * @return array<string, IACPSearchResultProvider>
+     */
+    public function getProviders(): array
+    {
+        return $this->providers;
+    }
+}
diff --git a/wcfsetup/install/files/lib/system/WCFACP.class.php b/wcfsetup/install/files/lib/system/WCFACP.class.php
index a2cd491b7a5..ffb5c77cd49 100644
--- a/wcfsetup/install/files/lib/system/WCFACP.class.php
+++ b/wcfsetup/install/files/lib/system/WCFACP.class.php
@@ -4,9 +4,9 @@
 
 use Laminas\Diactoros\Uri;
 use wcf\system\application\ApplicationHandler;
-use wcf\system\cache\builder\ACPSearchProviderCacheBuilder;
 use wcf\system\event\EventHandler;
 use wcf\system\request\RouteHandler;
+use wcf\system\search\acp\ACPSearchHandler;
 use wcf\system\session\ACPSessionFactory;
 use wcf\system\session\SessionHandler;
 use wcf\system\template\ACPTemplateEngine;
@@ -170,9 +170,9 @@ protected function assignDefaultTemplateVariables(): void
 
         // available acp search providers
         $availableAcpSearchProviders = [];
-        foreach (ACPSearchProviderCacheBuilder::getInstance()->getData() as $searchProvider) {
-            $availableAcpSearchProviders[$searchProvider->providerName] = self::getLanguage()->get(
-                'wcf.acp.search.provider.' . $searchProvider->providerName
+        foreach (ACPSearchHandler::getInstance()->getProviderNames() as $providerName) {
+            $availableAcpSearchProviders[$providerName] = self::getLanguage()->get(
+                'wcf.acp.search.provider.' . $providerName
             );
         }
         \asort($availableAcpSearchProviders);
diff --git a/wcfsetup/install/files/lib/system/cache/builder/ACPSearchProviderCacheBuilder.class.php b/wcfsetup/install/files/lib/system/cache/builder/ACPSearchProviderCacheBuilder.class.php
index 72614fbe28b..bf6d9dd822b 100644
--- a/wcfsetup/install/files/lib/system/cache/builder/ACPSearchProviderCacheBuilder.class.php
+++ b/wcfsetup/install/files/lib/system/cache/builder/ACPSearchProviderCacheBuilder.class.php
@@ -10,6 +10,8 @@
  * @author  Alexander Ebert
  * @copyright   2001-2019 WoltLab GmbH
  * @license GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ *
+ * @deprecated 6.3
  */
 class ACPSearchProviderCacheBuilder extends AbstractCacheBuilder
 {
diff --git a/wcfsetup/install/files/lib/system/endpoint/controller/core/acp/SearchAcp.class.php b/wcfsetup/install/files/lib/system/endpoint/controller/core/acp/SearchAcp.class.php
new file mode 100644
index 00000000000..490482cc1fa
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/endpoint/controller/core/acp/SearchAcp.class.php
@@ -0,0 +1,83 @@
+<?php
+
+namespace wcf\system\endpoint\controller\core\acp;
+
+use Laminas\Diactoros\Response\JsonResponse;
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface;
+use wcf\http\Helper;
+use wcf\system\endpoint\GetRequest;
+use wcf\system\endpoint\IController;
+use wcf\system\exception\PermissionDeniedException;
+use wcf\system\search\acp\ACPSearchHandler;
+use wcf\system\WCF;
+
+/**
+ * Returns the ACP search results for a given query.
+ *
+ * @author      Marcel Werk
+ * @copyright   2001-2026 WoltLab GmbH
+ * @license     GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ * @since       6.3
+ */
+#[GetRequest('/core/acp/search')]
+final class SearchAcp implements IController
+{
+    #[\Override]
+    public function __invoke(ServerRequestInterface $request, array $variables): ResponseInterface
+    {
+        if (!WCF::getSession()->hasPermission('admin.general.canUseAcp')) {
+            throw new PermissionDeniedException();
+        }
+
+        $parameters = Helper::mapQueryParameters(
+            $request->getQueryParams(),
+            <<<'EOT'
+                array {
+                    query: non-empty-string,
+                    provider?: string,
+                }
+                EOT,
+        );
+
+        $results = ACPSearchHandler::getInstance()->search(
+            $parameters['query'],
+            20,
+            $parameters['provider'] ?? ''
+        );
+
+        $data = [];
+        foreach ($results as $resultList) {
+            $items = [];
+            foreach ($resultList as $item) {
+                $items[] = [
+                    'link' => $item->getLink(),
+                    'subtitle' => $item->getSubtitle(),
+                    'title' => $item->getTitle(),
+                ];
+            }
+
+            foreach ($items as $key => &$item) {
+                $double = false;
+                foreach ($items as $key2 => $item2) {
+                    if ($key !== $key2 && !\strcasecmp($item['title'], $item2['title'])) {
+                        $double = true;
+                        break;
+                    }
+                }
+
+                if (!$double) {
+                    unset($item['subtitle']);
+                }
+            }
+            unset($item);
+
+            $data[] = [
+                'items' => $items,
+                'title' => $resultList->getTitle(),
+            ];
+        }
+
+        return new JsonResponse(['results' => $data]);
+    }
+}
diff --git a/wcfsetup/install/files/lib/system/event/listener/AcpSearchProviderCollectingListener.class.php b/wcfsetup/install/files/lib/system/event/listener/AcpSearchProviderCollectingListener.class.php
new file mode 100644
index 00000000000..778daaaf3ce
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/event/listener/AcpSearchProviderCollectingListener.class.php
@@ -0,0 +1,38 @@
+<?php
+
+namespace wcf\system\event\listener;
+
+use wcf\event\acp\search\provider\ProviderCollecting;
+use wcf\system\search\acp\ArticleACPSearchResultProvider;
+use wcf\system\search\acp\BoxACPSearchResultProvider;
+use wcf\system\search\acp\MenuItemACPSearchResultProvider;
+use wcf\system\search\acp\OptionACPSearchResultProvider;
+use wcf\system\search\acp\PackageACPSearchResultProvider;
+use wcf\system\search\acp\PageACPSearchResultProvider;
+use wcf\system\search\acp\TrophyACPSearchResultProvider;
+use wcf\system\search\acp\UserACPSearchResultProvider;
+use wcf\system\search\acp\UserGroupOptionACPSearchResultProvider;
+
+/**
+ * Registers the built-in ACP search providers of the core.
+ *
+ * @author      Marcel Werk
+ * @copyright   2001-2026 WoltLab GmbH
+ * @license     GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ * @since       6.3
+ */
+final class AcpSearchProviderCollectingListener
+{
+    public function __invoke(ProviderCollecting $event): void
+    {
+        $event->register('com.woltlab.wcf.article', new ArticleACPSearchResultProvider());
+        $event->register('com.woltlab.wcf.box', new BoxACPSearchResultProvider());
+        $event->register('com.woltlab.wcf.menuItem', new MenuItemACPSearchResultProvider());
+        $event->register('com.woltlab.wcf.option', new OptionACPSearchResultProvider());
+        $event->register('com.woltlab.wcf.package', new PackageACPSearchResultProvider());
+        $event->register('com.woltlab.wcf.page', new PageACPSearchResultProvider());
+        $event->register('com.woltlab.wcf.trophy', new TrophyACPSearchResultProvider());
+        $event->register('com.woltlab.wcf.user', new UserACPSearchResultProvider());
+        $event->register('com.woltlab.wcf.userGroupOption', new UserGroupOptionACPSearchResultProvider());
+    }
+}
diff --git a/wcfsetup/install/files/lib/system/package/plugin/ACPSearchProviderPackageInstallationPlugin.class.php b/wcfsetup/install/files/lib/system/package/plugin/ACPSearchProviderPackageInstallationPlugin.class.php
index d3ba0b2ae7b..57defcc32cc 100644
--- a/wcfsetup/install/files/lib/system/package/plugin/ACPSearchProviderPackageInstallationPlugin.class.php
+++ b/wcfsetup/install/files/lib/system/package/plugin/ACPSearchProviderPackageInstallationPlugin.class.php
@@ -26,6 +26,8 @@
  * @author  Alexander Ebert
  * @copyright   2001-2019 WoltLab GmbH
  * @license GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ *
+ * @deprecated 6.3 Register providers through the `wcf\event\acp\search\provider\ProviderCollecting` event.
  */
 class ACPSearchProviderPackageInstallationPlugin extends AbstractXMLPackageInstallationPlugin implements
     IGuiPackageInstallationPlugin,
diff --git a/wcfsetup/install/files/lib/system/search/acp/ACPSearchHandler.class.php b/wcfsetup/install/files/lib/system/search/acp/ACPSearchHandler.class.php
index 8433bdf9c22..02fd07074cc 100644
--- a/wcfsetup/install/files/lib/system/search/acp/ACPSearchHandler.class.php
+++ b/wcfsetup/install/files/lib/system/search/acp/ACPSearchHandler.class.php
@@ -2,11 +2,13 @@
 
 namespace wcf\system\search\acp;
 
-use wcf\data\acp\search\provider\ACPSearchProvider;
+use wcf\event\acp\search\provider\ProviderCollecting;
 use wcf\system\application\ApplicationHandler;
 use wcf\system\cache\builder\ACPSearchProviderCacheBuilder;
+use wcf\system\event\EventHandler;
 use wcf\system\exception\ImplementationException;
 use wcf\system\SingletonFactory;
+use wcf\system\WCF;
 
 /**
  * Handles ACP Search.
@@ -24,22 +26,47 @@ class ACPSearchHandler extends SingletonFactory
     public $abbreviations = [];
 
     /**
-     * list of acp search provider
-     * @var ACPSearchProvider[]
+     * @var array<string, IACPSearchResultProvider>
      */
-    protected $cache;
+    private array $providers = [];
 
     #[\Override]
     protected function init()
     {
-        $this->cache = ACPSearchProviderCacheBuilder::getInstance()->getData();
+        $event = new ProviderCollecting();
+        EventHandler::getInstance()->fire($event);
+        foreach ($event->getProviders() as $providerName => $provider) {
+            $this->providers[$providerName] = $provider;
+        }
+
+        foreach (ACPSearchProviderCacheBuilder::getInstance()->getData() as $acpSearchProvider) {
+            if (isset($this->providers[$acpSearchProvider->providerName])) {
+                continue;
+            }
+
+            $className = $acpSearchProvider->className;
+            if (!\is_subclass_of($className, IACPSearchResultProvider::class)) {
+                throw new ImplementationException($className, IACPSearchResultProvider::class);
+            }
+
+            $this->providers[$acpSearchProvider->providerName] = new $className();
+        }
+
+        $language = WCF::getLanguage();
+        $collator = new \Collator($language->getLocale());
+        \uksort(
+            $this->providers,
+            static fn(string $a, string $b) => $collator->compare(
+                $language->get('wcf.acp.search.provider.' . $a),
+                $language->get('wcf.acp.search.provider.' . $b)
+            )
+        );
     }
 
     /**
      * Returns a list of search result collections for given query.
      *
      * @return  ACPSearchResultList[]
-     * @throws  ImplementationException
      */
     public function search(string $query, int $limit = 10, string $providerName = '')
     {
@@ -51,22 +78,15 @@ public function search(string $query, int $limit = 10, string $providerName = ''
         }
         $totalResultCount = 0;
 
-        foreach ($this->cache as $acpSearchProvider) {
-            if ($providerName && $acpSearchProvider->providerName != $providerName) {
+        foreach ($this->providers as $name => $provider) {
+            if ($providerName && $name !== $providerName) {
                 continue;
             }
 
-            $className = $acpSearchProvider->className;
-            if (!\is_subclass_of($className, IACPSearchResultProvider::class)) {
-                throw new ImplementationException($className, IACPSearchResultProvider::class);
-            }
-
-            /** @var IACPSearchResultProvider $provider */
-            $provider = new $className();
             $results = $provider->search($query);
 
             if (!empty($results)) {
-                $resultList = new ACPSearchResultList($acpSearchProvider->providerName);
+                $resultList = new ACPSearchResultList($name);
                 foreach ($results as $result) {
                     $resultList->addResult($result);
                 }
@@ -116,6 +136,17 @@ public function search(string $query, int $limit = 10, string $providerName = ''
         return $data;
     }
 
+    /**
+     * Returns the names of all registered ACP search providers in display order.
+     *
+     * @return string[]
+     * @since 6.3
+     */
+    public function getProviderNames(): array
+    {
+        return \array_keys($this->providers);
+    }
+
     /**
      * Returns a list of application abbreviations.
      *