diff --git a/web/src/app/browser/src/configuration.ts b/web/src/app/browser/src/configuration.ts
index 5d5907cd0e..3b23ba6e72 100644
--- a/web/src/app/browser/src/configuration.ts
+++ b/web/src/app/browser/src/configuration.ts
@@ -40,7 +40,7 @@ export class BrowserConfiguration extends EngineConfiguration {
     const ruleTransform = ruleBehavior.transcription.transform;
     if(!isEmptyTransform(ruleTransform)) {
       if(outputTarget instanceof DOMOutputTarget) {
-        dom.DOMEventHandlers.states.changed = true;
+        outputTarget.changed = true;
       }
     }
   }
diff --git a/web/src/app/browser/src/contextManager.ts b/web/src/app/browser/src/contextManager.ts
index 9eeac99a71..a8f533472d 100644
--- a/web/src/app/browser/src/contextManager.ts
+++ b/web/src/app/browser/src/contextManager.ts
@@ -2,10 +2,12 @@ import { type Keyboard, Mock } from '@keymanapp/keyboard-processor';
 import { type KeyboardStub } from 'keyman/engine/package-cache';
 import { CookieSerializer } from 'keyman/engine/dom-utils';
 import { PageContextAttachment } from 'keyman/engine/attachment';
+import { LegacyEventEmitter } from 'keyman/engine/events';
 import { DesignIFrame, OutputTarget, nestedInstanceOf } from 'keyman/engine/element-wrappers';
 import {
   ContextManagerBase,
-  type KeyboardInterface
+  type KeyboardInterface,
+  LegacyAPIEvents
 } from 'keyman/engine/main';
 import { BrowserConfiguration } from './configuration.js';
 import { FocusAssistant } from './context/focusAssistant.js';
@@ -102,6 +104,16 @@ export default class ContextManager extends ContextManagerBase<BrowserConfigurat
 
   private globalKeyboard: {keyboard: Keyboard, metadata: KeyboardStub};
 
+  private _eventsObj: () => LegacyEventEmitter<LegacyAPIEvents>;
+
+  constructor(engineConfig: BrowserConfiguration, eventsClosure: () => LegacyEventEmitter<LegacyAPIEvents>) {
+    super(engineConfig);
+  }
+
+  get apiEvents(): LegacyEventEmitter<LegacyAPIEvents> {
+    return this._eventsObj();
+  }
+
   initialize(): void {
     this.on('keyboardasyncload', (stub, completion) => {
       // TODO:  app/browser - display the loader UI if configured?
@@ -416,13 +428,19 @@ export default class ContextManager extends ContextManagerBase<BrowserConfigurat
     //   Ltarg=Ltarg.contentWindow.document.body; // And we only care about Ltarg b/c of finding the OutputTarget.
     // }
 
-    // Step 2:  Make it active.
+    // Save it for the event in step 3... but now, before we mutate the field's value!
+    const previousTarget = this.lastActiveTarget;
+
+    // Step 2:  Make the newly-focused control the active control, and thus the active context.
     this.setActiveTarget(target);
 
     // Step 3:  related events
 
     // //Execute external (UI) code needed on focus if required
-    // this.doControlFocused(LfocusTarg, this.keyman.domManager.lastActiveElement);
+    this.apiEvents.callEvent('controlfocused', {
+      target: target.getElement(),
+      activeControl: previousTarget.getElement()
+    });
 
     return true;
   }
@@ -450,8 +468,8 @@ export default class ContextManager extends ContextManagerBase<BrowserConfigurat
     }
 
     // Step 1: determine the corresponding OutputTarget instance.
-    let Ltarg = eventOutputTarget(e);
-    if (Ltarg == null) {
+    let target = eventOutputTarget(e);
+    if (target == null) {
       return true;
     }
 
@@ -465,8 +483,9 @@ export default class ContextManager extends ContextManagerBase<BrowserConfigurat
 
     // Step 3: Now that we've handled all prior-element maintenance, update the active and 'last-active element'.
     // (The "context target" state fields)
+    const previousTarget = this.activeTarget;
     this.currentTarget = null; // I3363 (Build 301)
-    this.mostRecentTarget = Ltarg;
+    this.mostRecentTarget = target;
 
     // Step 4: any and all related events
     /* If the KeymanWeb UI is active as a user changes controls, all UI-based effects
@@ -478,13 +497,30 @@ export default class ContextManager extends ContextManagerBase<BrowserConfigurat
     let activeKeyboard = this.activeKeyboard;
     const maintainingFocus = this.focusAssistant.maintainingFocus;
     if(!maintainingFocus && activeKeyboard) {
-      activeKeyboard.keyboard.notify(0, Ltarg, 0);  // I2187
+      activeKeyboard.keyboard.notify(0, target, 0);  // I2187
+    }
+    if(previousTarget && !this.activeTarget) {
+      this.emit('targetchange', null);
     }
 
-    // TODO:  these related events.
-    // this.doControlBlurred(Ltarg, e, maintainingFocus);
-    // this.doChangeEvent(Ltarg);
+    this.apiEvents.callEvent('controlblurred', {
+      target: target.getElement(),
+      event: e,
+      isActivating: maintainingFocus
+    });
+
+    // Is not an "API event"; it models a native browser event instead.
+    this.doChangeEvent(target);
     this.resetContext();
     return true;
   }
+
+  doChangeEvent(target: OutputTarget<any>) {
+    if(target.changed) {
+      let event = new Event('change', {"bubbles": true, "cancelable": false});
+      target.getElement().dispatchEvent(event);
+    }
+
+    target.changed = false;
+  }
 }
\ No newline at end of file
diff --git a/web/src/app/browser/src/keymanEngine.ts b/web/src/app/browser/src/keymanEngine.ts
index ef3a3a9431..587d7b4824 100644
--- a/web/src/app/browser/src/keymanEngine.ts
+++ b/web/src/app/browser/src/keymanEngine.ts
@@ -17,8 +17,10 @@ export class KeymanEngine extends KeymanEngineBase<ContextManager, KeyEventKeybo
     this.contextManager.restoreLastActiveTarget();
   }
 
-  constructor(worker: Worker, config: BrowserConfiguration) {
-    super(worker, config, new ContextManager(config));
+  constructor(worker: Worker, sourceUri: string) {
+    const config = new BrowserConfiguration(sourceUri);  // currently set to perform device auto-detect.
+
+    super(worker, config, new ContextManager(config, () => this.legacyAPIEvents));
 
     // Scrolls the document-body to ensure that a focused element remains visible after the OSK appears.
     this.contextManager.on('targetchange', (target: OutputTarget<any>) => {
diff --git a/web/src/engine/element-wrappers/src/outputTarget.ts b/web/src/engine/element-wrappers/src/outputTarget.ts
index 1ef15dd46f..e7640b36d5 100644
--- a/web/src/engine/element-wrappers/src/outputTarget.ts
+++ b/web/src/engine/element-wrappers/src/outputTarget.ts
@@ -5,6 +5,12 @@ export default abstract class OutputTarget<EventMap extends EventEmitter.ValidEv
   // JS/TS can't do true multiple inheritance, so we maintain class events on a readonly field.
   public readonly events: EventEmitter<EventMap, this> = new EventEmitter<EventMap, this>();
 
+  /**
+   * A field that may be used to track whether or not the represented context has changed over an
+   * arbitrary period of time.
+   */
+  public changed = false;
+
   /**
    * Returns the underlying element / document modeled by the wrapper.
    */
diff --git a/web/src/engine/main/src/index.ts b/web/src/engine/main/src/index.ts
index e04b2343bc..5a7f0c60ae 100644
--- a/web/src/engine/main/src/index.ts
+++ b/web/src/engine/main/src/index.ts
@@ -3,4 +3,5 @@ export { ContextManagerBase, ContextManagerConfiguration } from './contextManage
 export { default as HardKeyboard } from './hardKeyboard.js';
 export { default as KeyboardInterface } from './keyboardInterface.js';
 export { default as KeymanEngine } from './keymanEngine.js';
+export { LegacyAPIEvents } from './legacyAPIEvents.js';
 export { VariableStoreCookieSerializer } from './variableStoreCookieSerializer.js';
\ No newline at end of file
diff --git a/web/src/engine/main/src/keymanEngine.ts b/web/src/engine/main/src/keymanEngine.ts
index 54c391a49a..95e251b4ae 100644
--- a/web/src/engine/main/src/keymanEngine.ts
+++ b/web/src/engine/main/src/keymanEngine.ts
@@ -24,7 +24,7 @@ export default class KeymanEngine<
   readonly keyboardRequisitioner: KeyboardRequisitioner;
   readonly modelCache: ModelCache;
 
-  private legacyAPIEvents = new LegacyEventEmitter<LegacyAPIEvents>();
+  protected legacyAPIEvents = new LegacyEventEmitter<LegacyAPIEvents>();
   private _hardKeyboard: HardKeyboard;
   private _osk: OSKView;
 
diff --git a/web/src/engine/main/src/legacyAPIEvents.ts b/web/src/engine/main/src/legacyAPIEvents.ts
index aa16141726..b30957c8d1 100644
--- a/web/src/engine/main/src/legacyAPIEvents.ts
+++ b/web/src/engine/main/src/legacyAPIEvents.ts
@@ -26,6 +26,23 @@ export interface LegacyAPIEvents extends LegacyEventMap {
     languageCode: string
   }) => boolean;
 
+  'controlfocused': (p: {
+    /**
+     * The element gaining focus
+     */
+    target: HTMLElement,
+    /**
+     * The previous element to have focus
+     */
+    activeControl: HTMLElement
+  }) => boolean;
+
+  'controlblurred': (p: {
+    target: HTMLElement,
+    event: FocusEvent,
+    isActivating: boolean
+  }) => boolean;
+
   // TODO:  more of the documented API events.  Note that any remaining events not seen here
   //        yet go unused within the mobile apps.
 }
\ No newline at end of file
diff --git a/web/src/engine/namespaced-main/dom/domEventHandlers.ts b/web/src/engine/namespaced-main/dom/domEventHandlers.ts
index fdfd5946dc..912e32cbae 100644
--- a/web/src/engine/namespaced-main/dom/domEventHandlers.ts
+++ b/web/src/engine/namespaced-main/dom/domEventHandlers.ts
@@ -54,49 +54,6 @@ namespace com.keyman.dom {
 
     // Universal DOM event handlers (both desktop + touch)
 
-    /**
-     * Function     doControlFocused
-     * Scope        Private
-     * @param       {Object}            _target         element gaining focus
-     * @param       {Object}            _activeControl  currently active control
-     * @return      {boolean}
-     * Description  Execute external (UI) code needed on focus
-     */
-    doControlFocused(_target: HTMLElement, _activeControl: HTMLElement): boolean {
-      var p={};
-      p['target']=_target;
-      p['activeControl']=_activeControl;
-
-      return this.keyman.util.callEvent('kmw.controlfocused',p);
-    }
-
-    /**
-     * Function     doControlBlurred
-     * Scope        Private
-     * @param       {Object}            _target       element losing focus
-     * @param       {Event}             _event        event object
-     * @param       {(boolean|number)}  _isActivating activation state
-     * @return      {boolean}
-     * Description  Execute external (UI) code needed on blur
-     */
-    doControlBlurred(_target: HTMLElement, _event: Event, _isActivating: boolean|number): boolean {
-      var p={};
-      p['target']=_target;
-      p['event']=_event;
-      p['isActivating']=_isActivating;
-
-      return this.keyman.util.callEvent('kmw.controlblurred',p);
-    }
-
-    doChangeEvent(_target: HTMLElement) {
-      if(DOMEventHandlers.states.changed) {
-        let event = new Event('change', {"bubbles": true, "cancelable": false});
-        _target.dispatchEvent(event);
-      }
-
-      DOMEventHandlers.states.changed = false;
-    }
-
     /**
      * Function     _KeyDown
      * Scope        Private