diff --git a/mobile/android/app/geckoview-prefs.js b/mobile/android/app/geckoview-prefs.js
index 8da10fea4aeb..f46fa8a80739 100644
--- a/mobile/android/app/geckoview-prefs.js
+++ b/mobile/android/app/geckoview-prefs.js
@@ -399,9 +399,6 @@ pref("signon.firefoxRelay.feature", "not available");
 
 pref("signon.showAutoCompleteFooter", true);
 
-// Delegate autocomplete to GeckoView (bug 1618058)
-pref("toolkit.autocomplete.delegate", true);
-
 // Locked because any other value would break GeckoView
 pref("toolkit.defaultChromeURI", "chrome://geckoview/content/geckoview.xhtml", locked);
 
diff --git a/toolkit/actors/AutoCompleteParent.sys.mjs b/toolkit/actors/AutoCompleteParent.sys.mjs
index 43c437769662..4dd0292d364d 100644
--- a/toolkit/actors/AutoCompleteParent.sys.mjs
+++ b/toolkit/actors/AutoCompleteParent.sys.mjs
@@ -2,17 +2,10 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";
+import { AppConstants } from "resource://gre/modules/AppConstants.sys.mjs";
 
 const lazy = {};
 
-XPCOMUtils.defineLazyPreferenceGetter(
-  lazy,
-  "DELEGATE_AUTOCOMPLETE",
-  "toolkit.autocomplete.delegate",
-  false
-);
-
 ChromeUtils.defineESModuleGetters(lazy, {
   GeckoViewAutocomplete: "resource://gre/modules/GeckoViewAutocomplete.sys.mjs",
   setTimeout: "resource://gre/modules/Timer.sys.mjs",
@@ -378,7 +371,7 @@ export class AutoCompleteParent extends JSWindowActorParent {
 
     if (
       !browser ||
-      (!lazy.DELEGATE_AUTOCOMPLETE && !browser.autoCompletePopup)
+      (!AppConstants.MOZ_GECKOVIEW && !browser.autoCompletePopup)
     ) {
       // If there is no browser or popup, just make sure that the popup has been closed.
       if (this.openedPopup) {
@@ -414,7 +407,7 @@ export class AutoCompleteParent extends JSWindowActorParent {
       case "AutoComplete:MaybeOpenPopup": {
         let { results, rect, dir, inputElementIdentifier, formOrigin } =
           message.data;
-        if (lazy.DELEGATE_AUTOCOMPLETE) {
+        if (AppConstants.MOZ_GECKOVIEW) {
           lazy.GeckoViewAutocomplete.delegateSelection({
             browsingContext: this.browsingContext,
             options: results,
@@ -439,7 +432,7 @@ export class AutoCompleteParent extends JSWindowActorParent {
       }
 
       case "AutoComplete:ClosePopup": {
-        if (lazy.DELEGATE_AUTOCOMPLETE) {
+        if (AppConstants.MOZ_GECKOVIEW) {
           lazy.GeckoViewAutocomplete.delegateDismiss();
           break;
         }
diff --git a/toolkit/components/formautofill/FormAutofillChild.sys.mjs b/toolkit/components/formautofill/FormAutofillChild.sys.mjs
index ef4be1714e94..cba43b0fe98f 100644
--- a/toolkit/components/formautofill/FormAutofillChild.sys.mjs
+++ b/toolkit/components/formautofill/FormAutofillChild.sys.mjs
@@ -2,7 +2,6 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";
 import { AppConstants } from "resource://gre/modules/AppConstants.sys.mjs";
 
 const lazy = {};
@@ -26,13 +25,6 @@ ChromeUtils.defineESModuleGetters(lazy, {
   FORM_SUBMISSION_REASON: "resource://gre/actors/FormHandlerChild.sys.mjs",
 });
 
-XPCOMUtils.defineLazyPreferenceGetter(
-  lazy,
-  "DELEGATE_AUTOCOMPLETE",
-  "toolkit.autocomplete.delegate",
-  false
-);
-
 /**
  * Handles content's interactions for the frame.
  */
@@ -413,7 +405,7 @@ export class FormAutofillChild extends JSWindowActorChild {
     }
 
     if (
-      lazy.DELEGATE_AUTOCOMPLETE ||
+      AppConstants.MOZ_GECKOVIEW ||
       !lazy.FormAutofillContent.savedFieldNames
     ) {
       this.debug("onFocusIn: savedFieldNames are not known yet");