diff --git a/packages/ckeditor5-list/src/list/converters.ts b/packages/ckeditor5-list/src/list/converters.ts
index 050dba45f45..4b50fe86e35 100644
--- a/packages/ckeditor5-list/src/list/converters.ts
+++ b/packages/ckeditor5-list/src/list/converters.ts
@@ -349,6 +349,11 @@ export function listItemDowncastConverter(
 			return;
 		}
 
+		const options = {
+			...conversionApi.options,
+			dataPipeline
+		};
+
 		// Use positions mapping instead of mapper.toViewElement( listItem ) to find outermost view element.
 		// This is for cases when mapping is using inner view element like in the code blocks (pre > code).
 		const viewElement = findMappedViewElement( listItem, mapper, model )!;
@@ -360,10 +365,10 @@ export function listItemDowncastConverter(
 		unwrapListItemBlock( viewElement, writer );
 
 		// Insert custom item marker.
-		const viewRange = insertCustomMarkerElements( listItem, viewElement, strategies, writer, { dataPipeline } );
+		const viewRange = insertCustomMarkerElements( listItem, viewElement, strategies, writer, options );
 
 		// Then wrap them with the new list wrappers (UL, OL, LI).
-		wrapListItemBlock( listItem, viewRange, strategies, writer, conversionApi.options );
+		wrapListItemBlock( listItem, viewRange, strategies, writer, options );
 	};
 }
 
diff --git a/packages/ckeditor5-list/src/listformatting/listitemboldintegration.ts b/packages/ckeditor5-list/src/listformatting/listitemboldintegration.ts
index 695af10b6d2..e1ac5821886 100644
--- a/packages/ckeditor5-list/src/listformatting/listitemboldintegration.ts
+++ b/packages/ckeditor5-list/src/listformatting/listitemboldintegration.ts
@@ -8,6 +8,7 @@
  */
 
 import { Plugin } from 'ckeditor5/src/core.js';
+import { env } from 'ckeditor5/src/utils.js';
 
 import { ListEditing } from '../list/listediting.js';
 import type { ListFormatting } from '../listformatting.js';
@@ -58,9 +59,14 @@ export class ListItemBoldIntegration extends Plugin {
 			scope: 'item',
 			attributeName: 'listItemBold',
 
-			setAttributeOnDowncast( writer, value, viewElement ) {
+			setAttributeOnDowncast( writer, value, viewElement, options ) {
 				if ( value ) {
 					writer.addClass( 'ck-list-marker-bold', viewElement );
+
+					// See: https://github.com/ckeditor/ckeditor5/issues/18790.
+					if ( env.isSafari && !( options && options.dataPipeline ) ) {
+						writer.setStyle( '--ck-content-list-marker-dummy-bold', '0', viewElement );
+					}
 				}
 			}
 		} );
diff --git a/packages/ckeditor5-list/src/listformatting/listitemfontsizeintegration.ts b/packages/ckeditor5-list/src/listformatting/listitemfontsizeintegration.ts
index b11a49b4fd0..43416e5ce11 100644
--- a/packages/ckeditor5-list/src/listformatting/listitemfontsizeintegration.ts
+++ b/packages/ckeditor5-list/src/listformatting/listitemfontsizeintegration.ts
@@ -9,6 +9,7 @@
 
 import { Plugin } from 'ckeditor5/src/core.js';
 import type { ViewElement } from 'ckeditor5/src/engine.js';
+import { env } from 'ckeditor5/src/utils.js';
 import { _normalizeFontSizeOptions } from '@ckeditor/ckeditor5-font';
 
 import { ListEditing } from '../list/listediting.js';
@@ -62,7 +63,7 @@ export class ListItemFontSizeIntegration extends Plugin {
 			scope: 'item',
 			attributeName: 'listItemFontSize',
 
-			setAttributeOnDowncast( writer, value: string, viewElement ) {
+			setAttributeOnDowncast( writer, value: string, viewElement, options ) {
 				if ( value ) {
 					const fontSizeOption = normalizedFontSizeOptions.find( option => option.model == value );
 
@@ -73,6 +74,11 @@ export class ListItemFontSizeIntegration extends Plugin {
 						}
 						else if ( fontSizeOption.view.classes ) {
 							writer.addClass( `ck-list-marker-font-size-${ value }`, viewElement );
+
+							// See: https://github.com/ckeditor/ckeditor5/issues/18790.
+							if ( env.isSafari && !( options && options.dataPipeline ) ) {
+								writer.setStyle( '--ck-content-list-marker-dummy-font-size', '0', viewElement );
+							}
 						}
 					} else {
 						writer.addClass( 'ck-list-marker-font-size', viewElement );
diff --git a/packages/ckeditor5-list/src/listformatting/listitemitalicintegration.ts b/packages/ckeditor5-list/src/listformatting/listitemitalicintegration.ts
index 3398b2a5ee9..1bb5e5db689 100644
--- a/packages/ckeditor5-list/src/listformatting/listitemitalicintegration.ts
+++ b/packages/ckeditor5-list/src/listformatting/listitemitalicintegration.ts
@@ -8,6 +8,7 @@
  */
 
 import { Plugin } from 'ckeditor5/src/core.js';
+import { env } from 'ckeditor5/src/utils.js';
 
 import { ListEditing } from '../list/listediting.js';
 import type { ListFormatting } from '../listformatting.js';
@@ -58,9 +59,14 @@ export class ListItemItalicIntegration extends Plugin {
 			scope: 'item',
 			attributeName: 'listItemItalic',
 
-			setAttributeOnDowncast( writer, value, viewElement ) {
+			setAttributeOnDowncast( writer, value, viewElement, options ) {
 				if ( value ) {
 					writer.addClass( 'ck-list-marker-italic', viewElement );
+
+					// See: https://github.com/ckeditor/ckeditor5/issues/18790.
+					if ( env.isSafari && !( options && options.dataPipeline ) ) {
+						writer.setStyle( '--ck-content-list-marker-dummy-italic', '0', viewElement );
+					}
 				}
 			}
 		} );
diff --git a/packages/ckeditor5-list/tests/listformatting/listitemboldintegration.js b/packages/ckeditor5-list/tests/listformatting/listitemboldintegration.js
index a2b9051972b..a8ecd0f3396 100644
--- a/packages/ckeditor5-list/tests/listformatting/listitemboldintegration.js
+++ b/packages/ckeditor5-list/tests/listformatting/listitemboldintegration.js
@@ -15,6 +15,7 @@ import { ClipboardPipeline } from '@ckeditor/ckeditor5-clipboard/src/clipboardpi
 import { testUtils } from '@ckeditor/ckeditor5-core/tests/_utils/utils.js';
 import { _setModelData, _getModelData, _stringifyModel } from '@ckeditor/ckeditor5-engine/src/dev-utils/model.js';
 import { _getViewData } from '@ckeditor/ckeditor5-engine/src/dev-utils/view.js';
+import { env } from 'ckeditor5/src/utils.js';
 
 import { stubUid } from '../list/_utils/uid.js';
 import { ListEditing } from '../../src/list/listediting.js';
@@ -336,6 +337,35 @@ describe( 'ListItemBoldIntegration', () => {
 				'</ul>'
 			);
 		} );
+
+		// See: https://github.com/ckeditor/ckeditor5/issues/18790.
+		it( 'should add dummy style for a Safari glitch (in editing pipeline only)', () => {
+			sinon.stub( env, 'isSafari' ).value( true );
+
+			_setModelData( model,
+				'<paragraph listIndent="0" listItemId="a" listItemBold="true" listType="bulleted">' +
+					'<$text bold="true">foo</$text>' +
+				'</paragraph>'
+			);
+
+			expect( _getViewData( view, { withoutSelection: true } ) ).to.equal(
+				'<ul>' +
+					'<li class="ck-list-marker-bold" style="--ck-content-list-marker-dummy-bold:0">' +
+						'<span class="ck-list-bogus-paragraph">' +
+							'<strong>foo</strong>' +
+						'</span>' +
+					'</li>' +
+				'</ul>'
+			);
+
+			expect( editor.getData( { skipListItemIds: true } ) ).to.equalMarkup(
+				'<ul>' +
+					'<li class="ck-list-marker-bold">' +
+						'<strong>foo</strong>' +
+					'</li>' +
+				'</ul>'
+			);
+		} );
 	} );
 
 	describe( 'upcast', () => {
diff --git a/packages/ckeditor5-list/tests/listformatting/listitemfontsizeintegration.js b/packages/ckeditor5-list/tests/listformatting/listitemfontsizeintegration.js
index 5317d357873..8e208408218 100644
--- a/packages/ckeditor5-list/tests/listformatting/listitemfontsizeintegration.js
+++ b/packages/ckeditor5-list/tests/listformatting/listitemfontsizeintegration.js
@@ -15,6 +15,7 @@ import { ClipboardPipeline } from '@ckeditor/ckeditor5-clipboard';
 import { testUtils } from '@ckeditor/ckeditor5-core/tests/_utils/utils.js';
 import { _setModelData, _getModelData, _stringifyModel } from '@ckeditor/ckeditor5-engine/src/dev-utils/model.js';
 import { _getViewData } from '@ckeditor/ckeditor5-engine/src/dev-utils/view.js';
+import { env } from 'ckeditor5/src/utils.js';
 
 import { stubUid } from '../list/_utils/uid.js';
 import { ListEditing } from '../../src/list/listediting.js';
@@ -372,6 +373,35 @@ describe( 'ListItemFontSizeIntegration', () => {
 					'</ul>'
 				);
 			} );
+
+			// See: https://github.com/ckeditor/ckeditor5/issues/18790.
+			it( 'should add dummy style for a Safari glitch (in editing pipeline only)', () => {
+				sinon.stub( env, 'isSafari' ).value( true );
+
+				_setModelData( model,
+					'<paragraph listIndent="0" listItemId="a" listItemFontSize="tiny" listType="bulleted">' +
+						'<$text fontSize="tiny">foo</$text>' +
+					'</paragraph>'
+				);
+
+				expect( _getViewData( view, { withoutSelection: true } ) ).to.equal(
+					'<ul>' +
+						'<li class="ck-list-marker-font-size-tiny" style="--ck-content-list-marker-dummy-font-size:0">' +
+							'<span class="ck-list-bogus-paragraph">' +
+								'<span class="text-tiny">foo</span>' +
+							'</span>' +
+						'</li>' +
+					'</ul>'
+				);
+
+				expect( editor.getData( { skipListItemIds: true } ) ).to.equalMarkup(
+					'<ul>' +
+						'<li class="ck-list-marker-font-size-tiny">' +
+							'<span class="text-tiny">foo</span>' +
+						'</li>' +
+					'</ul>'
+				);
+			} );
 		} );
 
 		describe( 'upcast', () => {
diff --git a/packages/ckeditor5-list/tests/listformatting/listitemitalicintegration.js b/packages/ckeditor5-list/tests/listformatting/listitemitalicintegration.js
index 33bce2e3e2a..0540b889131 100644
--- a/packages/ckeditor5-list/tests/listformatting/listitemitalicintegration.js
+++ b/packages/ckeditor5-list/tests/listformatting/listitemitalicintegration.js
@@ -15,6 +15,7 @@ import { ClipboardPipeline } from '@ckeditor/ckeditor5-clipboard';
 import { testUtils } from '@ckeditor/ckeditor5-core/tests/_utils/utils.js';
 import { _setModelData, _getModelData, _stringifyModel } from '@ckeditor/ckeditor5-engine/src/dev-utils/model.js';
 import { _getViewData } from '@ckeditor/ckeditor5-engine/src/dev-utils/view.js';
+import { env } from 'ckeditor5/src/utils.js';
 
 import { stubUid } from '../list/_utils/uid.js';
 import { ListEditing } from '../../src/list/listediting.js';
@@ -336,6 +337,35 @@ describe( 'ListItemItalicIntegration', () => {
 				'</ul>'
 			);
 		} );
+
+		// See: https://github.com/ckeditor/ckeditor5/issues/18790.
+		it( 'should add dummy style for a Safari glitch (in editing pipeline only)', () => {
+			sinon.stub( env, 'isSafari' ).value( true );
+
+			_setModelData( model,
+				'<paragraph listIndent="0" listItemId="a" listItemItalic="true" listType="bulleted">' +
+					'<$text italic="true">foo</$text>' +
+				'</paragraph>'
+			);
+
+			expect( _getViewData( view, { withoutSelection: true } ) ).to.equal(
+				'<ul>' +
+					'<li class="ck-list-marker-italic" style="--ck-content-list-marker-dummy-italic:0">' +
+						'<span class="ck-list-bogus-paragraph">' +
+							'<i>foo</i>' +
+						'</span>' +
+					'</li>' +
+				'</ul>'
+			);
+
+			expect( editor.getData( { skipListItemIds: true } ) ).to.equalMarkup(
+				'<ul>' +
+					'<li class="ck-list-marker-italic">' +
+						'<i>foo</i>' +
+					'</li>' +
+				'</ul>'
+			);
+		} );
 	} );
 
 	describe( 'upcast', () => {