diff --git a/docs/features/watchdog.md b/docs/features/watchdog.md
index 4c51754..81b7255 100644
--- a/docs/features/watchdog.md
+++ b/docs/features/watchdog.md
@@ -54,7 +54,7 @@ In other words, your goal is to create a watchdog instance and make the watchdog
 
 ### Controlling editor creation and destruction
 
-For more control over the creation and destruction of editor instances, you can use the {@link module:watchdog/watchdog~Watchdog#setCreator `Watchdog#setCreator()`} and {@link module:watchdog/watchdog~Watchdog#setDestructor `Watchdog#setDestructor()`} methods:
+For more control over the creation and destruction of editor instances, you can use the {@link module:watchdog/watchdog~Watchdog#setCreator `Watchdog#setCreator()`} and, if needed, the {@link module:watchdog/watchdog~Watchdog#setDestructor `Watchdog#setDestructor()`} methods:
 
 ```js
 // Instantiate the watchdog manually (do not use the for() helper).
@@ -81,6 +81,10 @@ watchdog.setDestructor( editor => {
 watchdog.create( elementOrData, editorConfig );
 ```
 
+<info-box>
+	The default (not overridden) editor destructor is the `editor => editor.destroy()` function.
+</info-box>
+
 ### API
 
 Other useful {@link module:watchdog/watchdog~Watchdog methods, properties and events}:
diff --git a/src/watchdog.js b/src/watchdog.js
index 8959a9d..9a55c1c 100644
--- a/src/watchdog.js
+++ b/src/watchdog.js
@@ -135,6 +135,7 @@ export default class Watchdog {
 		 * @member {Function} #_destructor
 		 * @see #setDestructor
 		 */
+		this._destructor = editor => editor.destroy();
 
 		/**
 		 * The latest saved editor data represented as a root name -> root data object.
@@ -189,9 +190,18 @@ export default class Watchdog {
 
 	/**
 	 * Sets the function that is responsible for the editor destruction.
+	 * Overrides the default destruction function, which destroys only the editor instance.
 	 * It expects a function that should return a promise or `undefined`.
 	 *
-	 *		watchdog.setDestructor( editor => editor.destroy() );
+	 *		watchdog.setDestructor( editor => {
+	 *			// Do something before the editor is destroyed.
+	 *
+	 *			return editor
+	 *				.destroy()
+	 *				.then( () => {
+	 *					// Do something after the editor is destroyed.
+	 *				} );
+	 *		} );
 	 *
 	 * @param {Function} destructor
 	 */
@@ -223,20 +233,6 @@ export default class Watchdog {
 			);
 		}
 
-		if ( !this._destructor ) {
-			/**
-			 * The watchdog's editor destructor is not defined. Define it by using
-			 * {@link module:watchdog/watchdog~Watchdog#setDestructor `Watchdog#setDestructor()`} or
-			 * the {@link module:watchdog/watchdog~Watchdog.for `Watchdog.for()`} helper.
-			 *
-			 * @error watchdog-destructor-not-defined
-			 */
-			throw new CKEditorError(
-				'watchdog-destructor-not-defined: The watchdog\'s editor destructor is not defined.',
-				null
-			);
-		}
-
 		this._elementOrData = elementOrData;
 
 		// Clone configuration because it might be shared within multiple watchdog instances. Otherwise,
@@ -473,7 +469,6 @@ export default class Watchdog {
 		const watchdog = new Watchdog( watchdogConfig );
 
 		watchdog.setCreator( ( elementOrData, config ) => Editor.create( elementOrData, config ) );
-		watchdog.setDestructor( editor => editor.destroy() );
 
 		return watchdog;
 	}
diff --git a/tests/watchdog.js b/tests/watchdog.js
index 4200f0b..6c1e382 100644
--- a/tests/watchdog.js
+++ b/tests/watchdog.js
@@ -34,7 +34,6 @@ describe( 'Watchdog', () => {
 			const editorDestroySpy = sinon.spy( ClassicTestEditor.prototype, 'destroy' );
 
 			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			return watchdog.create( element, {} )
 				.then( () => {
@@ -51,7 +50,6 @@ describe( 'Watchdog', () => {
 
 		it( 'should throw an error when the creator is not defined', () => {
 			const watchdog = new Watchdog();
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			expectToThrowCKEditorError(
 				() => watchdog.create(),
@@ -60,21 +58,16 @@ describe( 'Watchdog', () => {
 			);
 		} );
 
-		it( 'should throw an error when the destructor is not defined', () => {
+		it( 'should not throw an error when the destructor is not defined', () => {
 			const watchdog = new Watchdog();
 			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
 
-			expectToThrowCKEditorError(
-				() => watchdog.create(),
-				/^watchdog-destructor-not-defined/,
-				null
-			);
+			expect( () => watchdog.create() ).to.not.throw();
 		} );
 
 		it( 'should properly copy the config', () => {
 			const watchdog = new Watchdog();
 			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			const config = {
 				foo: [],
@@ -91,7 +84,6 @@ describe( 'Watchdog', () => {
 			const watchdog = new Watchdog();
 
 			watchdog.setCreator( ( data, config ) => ClassicTestEditor.create( data, config ) );
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			// sinon.stub( window, 'onerror' ).value( undefined ); and similar do not work.
 			const originalErrorHandler = window.onerror;
@@ -166,7 +158,6 @@ describe( 'Watchdog', () => {
 				ClassicTestEditor.create( el )
 					.then( () => Promise.reject( new Error( 'foo' ) ) )
 			);
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			return watchdog.create( element ).then(
 				() => { throw new Error( '`watchdog.create()` should throw an error.' ); },
@@ -199,7 +190,6 @@ describe( 'Watchdog', () => {
 			const watchdog = new Watchdog();
 
 			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			// sinon.stub( window, 'onerror' ).value( undefined ); and similar do not work.
 			const originalErrorHandler = window.onerror;
@@ -228,7 +218,6 @@ describe( 'Watchdog', () => {
 			const watchdog = new Watchdog();
 
 			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			// sinon.stub( window, 'onerror' ).value( undefined ); and similar do not work.
 			const originalErrorHandler = window.onerror;
@@ -251,7 +240,6 @@ describe( 'Watchdog', () => {
 			const watchdog = new Watchdog();
 
 			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			const editorErrorSpy = sinon.spy();
 			watchdog.on( 'error', editorErrorSpy );
@@ -322,7 +310,6 @@ describe( 'Watchdog', () => {
 			const watchdog = new Watchdog();
 
 			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			// sinon.stub( window, 'onerror' ).value( undefined ); and similar do not work.
 			const originalErrorHandler = window.onerror;
@@ -345,7 +332,6 @@ describe( 'Watchdog', () => {
 			const watchdog = new Watchdog();
 
 			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			// sinon.stub( window, 'onerror' ).value( undefined ); and similar do not work.
 			const originalErrorHandler = window.onerror;
@@ -378,7 +364,6 @@ describe( 'Watchdog', () => {
 			const watchdog = new Watchdog();
 
 			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			const errorSpy = sinon.spy();
 			watchdog.on( 'error', errorSpy );
@@ -415,7 +400,6 @@ describe( 'Watchdog', () => {
 			const watchdog = new Watchdog( { crashNumberLimit: 2, minimumNonErrorTimePeriod: 1000 } );
 
 			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			const errorSpy = sinon.spy();
 			watchdog.on( 'error', errorSpy );
@@ -451,7 +435,6 @@ describe( 'Watchdog', () => {
 			const watchdog = new Watchdog( { crashNumberLimit: 2, minimumNonErrorTimePeriod: 0 } );
 
 			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			const errorSpy = sinon.spy();
 			watchdog.on( 'error', errorSpy );
@@ -487,7 +470,6 @@ describe( 'Watchdog', () => {
 			const watchdog = new Watchdog();
 
 			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			// sinon.stub( window, 'onerror' ).value( undefined ); and similar do not work.
 			const originalErrorHandler = window.onerror;
@@ -519,7 +501,6 @@ describe( 'Watchdog', () => {
 			const watchdog = new Watchdog();
 
 			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			// sinon.stub( window, 'onerror' ).value( undefined ); and similar do not work.
 			const originalErrorHandler = window.onerror;
@@ -547,7 +528,6 @@ describe( 'Watchdog', () => {
 			const watchdog = new Watchdog();
 
 			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			// sinon.stub( window, 'onerror' ).value( undefined ); and similar do not work.
 			const originalErrorHandler = window.onerror;
@@ -575,7 +555,6 @@ describe( 'Watchdog', () => {
 			const watchdog = new Watchdog();
 
 			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			// sinon.stub( window, 'onerror' ).value( undefined ); and similar do not work.
 			const originalErrorHandler = window.onerror;
@@ -609,7 +588,6 @@ describe( 'Watchdog', () => {
 			const watchdog = new Watchdog();
 
 			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			// sinon.stub( window, 'onerror' ).value( undefined ); and similar do not work.
 			const originalErrorHandler = window.onerror;
@@ -648,7 +626,6 @@ describe( 'Watchdog', () => {
 			const watchdog = new Watchdog();
 
 			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
-			watchdog.setDestructor( editor => editor.destroy() );
 
 			// sinon.stub( window, 'onerror' ).value( undefined ); and similar do not work.
 			const originalErrorHandler = window.onerror;
@@ -698,6 +675,35 @@ describe( 'Watchdog', () => {
 				} );
 			} );
 		} );
+
+		it( 'should use the custom destructor if passed', () => {
+			const watchdog = new Watchdog();
+			const destructionSpy = sinon.spy();
+
+			watchdog.setCreator( ( el, config ) => ClassicTestEditor.create( el, config ) );
+			watchdog.setDestructor( editor => {
+				destructionSpy();
+				return editor.destroy();
+			} );
+
+			// sinon.stub( window, 'onerror' ).value( undefined ); and similar do not work.
+			const originalErrorHandler = window.onerror;
+			window.onerror = undefined;
+
+			return watchdog.create( element ).then( () => {
+				setTimeout( () => throwCKEditorError( 'foo', watchdog.editor ) );
+
+				return new Promise( res => {
+					watchdog.on( 'restart', () => {
+						window.onerror = originalErrorHandler;
+
+						sinon.assert.calledOnce( destructionSpy );
+
+						watchdog.destroy().then( res );
+					} );
+				} );
+			} );
+		} );
 	} );
 
 	describe( 'async error handling', () => {