diff --git a/src/ol/control/FullScreen.js b/src/ol/control/FullScreen.js
index b29a827cf0..ec61dadc56 100644
--- a/src/ol/control/FullScreen.js
+++ b/src/ol/control/FullScreen.js
@@ -80,6 +80,13 @@ class FullScreen extends Control {
       target: options.target,
     });
 
+    /***
+     * @type {import("../Observable").OnSignature<import("../Observable").EventTypes|
+     *     'enterfullscreen'|'leavefullscreen', import("../events/Event.js").default> &
+     *   import("../Observable").OnSignature<import("../ObjectEventType").Types, import("../Object").ObjectEvent>}
+     */
+    this.on;
+
     /**
      * @private
      * @type {string}
diff --git a/src/ol/control/MousePosition.js b/src/ol/control/MousePosition.js
index e6f47b5740..6da0741a9c 100644
--- a/src/ol/control/MousePosition.js
+++ b/src/ol/control/MousePosition.js
@@ -68,6 +68,13 @@ class MousePosition extends Control {
       target: options.target,
     });
 
+    /***
+     * @type {import("../Observable").OnSignature<import("../Observable").EventTypes, import("../events/Event.js").default> &
+     *   import("../Observable").OnSignature<import("../ObjectEventType").Types|
+     *     'change:coordinateFormat'|'change:projection', import("../Object").ObjectEvent>}
+     */
+    this.on;
+
     this.addChangeListener(PROJECTION, this.handleProjectionChanged_);
 
     if (options.coordinateFormat) {
diff --git a/src/ol/control/ScaleLine.js b/src/ol/control/ScaleLine.js
index 54b7465783..151ee230db 100644
--- a/src/ol/control/ScaleLine.js
+++ b/src/ol/control/ScaleLine.js
@@ -90,6 +90,13 @@ class ScaleLine extends Control {
       target: options.target,
     });
 
+    /***
+     * @type {import("../Observable").OnSignature<import("../Observable").EventTypes, import("../events/Event.js").default> &
+     *   import("../Observable").OnSignature<import("../ObjectEventType").Types|
+     *     'change:units', import("../Object").ObjectEvent>}
+     */
+    this.on;
+
     /**
      * @private
      * @type {HTMLElement}
diff --git a/src/ol/interaction/DragBox.js b/src/ol/interaction/DragBox.js
index 804777da95..1b758a27cc 100644
--- a/src/ol/interaction/DragBox.js
+++ b/src/ol/interaction/DragBox.js
@@ -112,6 +112,14 @@ class DragBox extends PointerInteraction {
   constructor(opt_options) {
     super();
 
+    /***
+     * @type {import("../Observable").OnSignature<import("../Observable").EventTypes, import("../events/Event.js").default> &
+     *   import("../Observable").OnSignature<import("../ObjectEventType").Types|
+     *     'change:active', import("../Object").ObjectEvent> &
+     *   import("../Observable").OnSignature<'boxcancel'|'boxdrag'|'boxend', DragBoxEvent>}
+     */
+    this.on;
+
     const options = opt_options ? opt_options : {};
 
     /**
diff --git a/src/ol/interaction/Draw.js b/src/ol/interaction/Draw.js
index b9f8f720c9..81e9ec4a4e 100644
--- a/src/ol/interaction/Draw.js
+++ b/src/ol/interaction/Draw.js
@@ -193,6 +193,14 @@ class Draw extends PointerInteraction {
 
     super(pointerOptions);
 
+    /***
+     * @type {import("../Observable").OnSignature<import("../Observable").EventTypes, import("../events/Event.js").default> &
+     *   import("../Observable").OnSignature<import("../ObjectEventType").Types|
+     *     'change:active', import("../Object").ObjectEvent> &
+     *   import("../Observable").OnSignature<'drawabort'|'drawend'|'drawstart', DrawEvent>}
+     */
+    this.on;
+
     /**
      * @type {boolean}
      * @private
diff --git a/src/ol/interaction/Extent.js b/src/ol/interaction/Extent.js
index 786605c259..1b7301e360 100644
--- a/src/ol/interaction/Extent.js
+++ b/src/ol/interaction/Extent.js
@@ -92,6 +92,14 @@ class Extent extends PointerInteraction {
 
     super(/** @type {import("./Pointer.js").Options} */ (options));
 
+    /***
+     * @type {import("../Observable").OnSignature<import("../Observable").EventTypes, import("../events/Event.js").default> &
+     *   import("../Observable").OnSignature<import("../ObjectEventType").Types|
+     *     'change:active', import("../Object").ObjectEvent> &
+     *   import("../Observable").OnSignature<'extentchanged', ExtentEvent>}
+     */
+    this.on;
+
     /**
      * Condition
      * @type {import("../events/condition.js").Condition}
diff --git a/src/ol/interaction/Interaction.js b/src/ol/interaction/Interaction.js
index 284b90aed6..caaa0c22b8 100644
--- a/src/ol/interaction/Interaction.js
+++ b/src/ol/interaction/Interaction.js
@@ -36,6 +36,13 @@ class Interaction extends BaseObject {
   constructor(opt_options) {
     super();
 
+    /***
+     * @type {import("../Observable").OnSignature<import("../Observable").EventTypes, import("../events/Event.js").default> &
+     *   import("../Observable").OnSignature<import("../ObjectEventType").Types|
+     *     'change:active', import("../Object").ObjectEvent>}
+     */
+    this.on;
+
     if (opt_options && opt_options.handleEvent) {
       this.handleEvent = opt_options.handleEvent;
     }
diff --git a/src/ol/interaction/Modify.js b/src/ol/interaction/Modify.js
index a0c99bb21e..8a5239e504 100644
--- a/src/ol/interaction/Modify.js
+++ b/src/ol/interaction/Modify.js
@@ -192,6 +192,14 @@ class Modify extends PointerInteraction {
   constructor(options) {
     super(/** @type {import("./Pointer.js").Options} */ (options));
 
+    /***
+     * @type {import("../Observable").OnSignature<import("../Observable").EventTypes, import("../events/Event.js").default> &
+     *   import("../Observable").OnSignature<import("../ObjectEventType").Types|
+     *     'change:active', import("../Object").ObjectEvent> &
+     *   import("../Observable").OnSignature<'modifyend'|'modifystart', ModifyEvent>}
+     */
+    this.on;
+
     /** @private */
     this.boundHandleFeatureChange_ = this.handleFeatureChange_.bind(this);
 
diff --git a/src/ol/interaction/Select.js b/src/ol/interaction/Select.js
index 95894e9b32..77ef66c194 100644
--- a/src/ol/interaction/Select.js
+++ b/src/ol/interaction/Select.js
@@ -156,6 +156,14 @@ class Select extends Interaction {
   constructor(opt_options) {
     super();
 
+    /***
+     * @type {import("../Observable").OnSignature<import("../Observable").EventTypes, import("../events/Event.js").default> &
+     *   import("../Observable").OnSignature<import("../ObjectEventType").Types|
+     *     'change:active', import("../Object").ObjectEvent> &
+     *   import("../Observable").OnSignature<'select', SelectEvent>}
+     */
+    this.on;
+
     const options = opt_options ? opt_options : {};
 
     /**
diff --git a/src/ol/interaction/Translate.js b/src/ol/interaction/Translate.js
index c0f9353527..9df11cb02d 100644
--- a/src/ol/interaction/Translate.js
+++ b/src/ol/interaction/Translate.js
@@ -126,6 +126,14 @@ class Translate extends PointerInteraction {
 
     super(/** @type {import("./Pointer.js").Options} */ (options));
 
+    /***
+     * @type {import("../Observable").OnSignature<import("../Observable").EventTypes, import("../events/Event.js").default> &
+     *   import("../Observable").OnSignature<import("../ObjectEventType").Types|
+     *     'change:active', import("../Object").ObjectEvent> &
+     *   import("../Observable").OnSignature<'translateend'|'translatestart'|'translating', TranslateEvent>}
+     */
+    this.on;
+
     /**
      * The last position we translated to.
      * @type {import("../coordinate.js").Coordinate}