diff --git a/src/Umbraco.Web.UI.Client/e2e/installer.spec.ts b/src/Umbraco.Web.UI.Client/e2e/installer.spec.ts
index 72bc7fa7e4..7e2a621f26 100644
--- a/src/Umbraco.Web.UI.Client/e2e/installer.spec.ts
+++ b/src/Umbraco.Web.UI.Client/e2e/installer.spec.ts
@@ -1,7 +1,7 @@
 const { rest } = window.MockServiceWorker;
 
 import { umbracoPath } from '@umbraco-cms/backoffice/utils';
-import { ProblemDetailsModel, RuntimeLevelModel, ServerStatusResponseModel } from '@umbraco-cms/backoffice/backend-api';
+import { ProblemDetails, RuntimeLevelModel, ServerStatusResponseModel } from '@umbraco-cms/backoffice/backend-api';
 import { expect, test } from './test.js';
 
 test.describe('installer tests', () => {
@@ -62,7 +62,7 @@ test.describe('installer tests', () => {
 					return res(
 						// Respond with a 200 status code
 						ctx.status(400),
-						ctx.json<ProblemDetailsModel>({
+						ctx.json<ProblemDetails>({
 							status: 400,
 							type: 'validation',
 							detail: 'Something went wrong',
diff --git a/src/Umbraco.Web.UI.Client/e2e/upgrader.spec.ts b/src/Umbraco.Web.UI.Client/e2e/upgrader.spec.ts
index 35728d313a..8e719ebec4 100644
--- a/src/Umbraco.Web.UI.Client/e2e/upgrader.spec.ts
+++ b/src/Umbraco.Web.UI.Client/e2e/upgrader.spec.ts
@@ -1,6 +1,6 @@
 const { rest } = window.MockServiceWorker;
 import { umbracoPath } from '@umbraco-cms/backoffice/utils';
-import { ProblemDetailsModel, RuntimeLevelModel, ServerStatusResponseModel } from '@umbraco-cms/backoffice/backend-api';
+import { ProblemDetails, RuntimeLevelModel, ServerStatusResponseModel } from '@umbraco-cms/backoffice/backend-api';
 import { expect, test } from './test.js';
 
 test.describe('upgrader tests', () => {
@@ -43,7 +43,7 @@ test.describe('upgrader tests', () => {
 				return res(
 					// Respond with a 200 status code
 					ctx.status(400),
-					ctx.json<ProblemDetailsModel>({
+					ctx.json<ProblemDetails>({
 						status: 400,
 						type: 'error',
 						detail: 'Something went wrong',
diff --git a/src/Umbraco.Web.UI.Client/src/apps/app/app-error.element.ts b/src/Umbraco.Web.UI.Client/src/apps/app/app-error.element.ts
index 0b3391ba90..ad0a977421 100644
--- a/src/Umbraco.Web.UI.Client/src/apps/app/app-error.element.ts
+++ b/src/Umbraco.Web.UI.Client/src/apps/app/app-error.element.ts
@@ -1,5 +1,5 @@
 import { css, html, nothing, customElement, property } from '@umbraco-cms/backoffice/external/lit';
-import type { ProblemDetailsModel } from '@umbraco-cms/backoffice/backend-api';
+import type { ProblemDetails } from '@umbraco-cms/backoffice/backend-api';
 import { UmbLitElement } from '@umbraco-cms/internal/lit-element';
 
 /**
@@ -23,7 +23,7 @@ export class UmbAppErrorElement extends UmbLitElement {
 	@property()
 	error?: unknown;
 
-	private renderProblemDetails = (problemDetails: ProblemDetailsModel) => html`
+	private renderProblemDetails = (problemDetails: ProblemDetails) => html`
 		<h2>${problemDetails.title}</h2>
 		<p>${problemDetails.detail}</p>
 		<pre>${problemDetails.stack}</pre>
@@ -35,7 +35,7 @@ export class UmbAppErrorElement extends UmbLitElement {
 		<pre>${error.stack}</pre>
 	`;
 
-	private isProblemDetails(error: unknown): error is ProblemDetailsModel {
+	private isProblemDetails(error: unknown): error is ProblemDetails {
 		return typeof error === 'object' && error !== null && 'detail' in error && 'title' in error;
 	}
 
diff --git a/src/Umbraco.Web.UI.Client/src/apps/installer/database/installer-database.element.ts b/src/Umbraco.Web.UI.Client/src/apps/installer/database/installer-database.element.ts
index 6245f82c74..e3448233c0 100644
--- a/src/Umbraco.Web.UI.Client/src/apps/installer/database/installer-database.element.ts
+++ b/src/Umbraco.Web.UI.Client/src/apps/installer/database/installer-database.element.ts
@@ -16,7 +16,7 @@ import {
 	DatabaseInstallResponseModel,
 	DatabaseSettingsPresentationModel,
 	InstallResource,
-	ProblemDetailsModel,
+	ProblemDetails,
 } from '@umbraco-cms/backoffice/backend-api';
 import { UmbLitElement } from '@umbraco-cms/internal/lit-element';
 import { tryExecute } from '@umbraco-cms/backoffice/resources';
@@ -216,7 +216,7 @@ export class UmbInstallerDatabaseElement extends UmbLitElement {
 		history.replaceState(null, '', 'section/content');
 	}
 
-	private _handleRejected(e: ProblemDetailsModel) {
+	private _handleRejected(e: ProblemDetails) {
 		this._installerContext?.setInstallStatus(e);
 	}
 
diff --git a/src/Umbraco.Web.UI.Client/src/apps/installer/error/installer-error.element.ts b/src/Umbraco.Web.UI.Client/src/apps/installer/error/installer-error.element.ts
index 75556a5aae..8fdb1a0233 100644
--- a/src/Umbraco.Web.UI.Client/src/apps/installer/error/installer-error.element.ts
+++ b/src/Umbraco.Web.UI.Client/src/apps/installer/error/installer-error.element.ts
@@ -1,12 +1,12 @@
 import { UmbInstallerContext, UMB_INSTALLER_CONTEXT_TOKEN } from '../installer.context.js';
 import { css, CSSResultGroup, html, nothing, customElement, state } from '@umbraco-cms/backoffice/external/lit';
-import { ProblemDetailsModel } from '@umbraco-cms/backoffice/backend-api';
+import { ProblemDetails } from '@umbraco-cms/backoffice/backend-api';
 import { UmbLitElement } from '@umbraco-cms/internal/lit-element';
 
 @customElement('umb-installer-error')
 export class UmbInstallerErrorElement extends UmbLitElement {
 	@state()
-	_error?: ProblemDetailsModel;
+	_error?: ProblemDetails;
 
 	private _installerContext?: UmbInstallerContext;
 
@@ -34,7 +34,7 @@ export class UmbInstallerErrorElement extends UmbLitElement {
 		this._installerContext?.reset();
 	}
 
-	private _renderError(error: ProblemDetailsModel) {
+	private _renderError(error: ProblemDetails) {
 		return html`
 			<p>Description: ${error.title}</p>
 			${error.errors ? this._renderErrors(error.errors) : nothing}
diff --git a/src/Umbraco.Web.UI.Client/src/apps/installer/installer.context.ts b/src/Umbraco.Web.UI.Client/src/apps/installer/installer.context.ts
index d81b13b572..a87c1fad4d 100644
--- a/src/Umbraco.Web.UI.Client/src/apps/installer/installer.context.ts
+++ b/src/Umbraco.Web.UI.Client/src/apps/installer/installer.context.ts
@@ -3,7 +3,7 @@ import {
 	InstallVResponseModel,
 	InstallResource,
 	InstallSettingsResponseModel,
-	ProblemDetailsModel,
+	ProblemDetails,
 	TelemetryLevelModel,
 } from '@umbraco-cms/backoffice/backend-api';
 import { tryExecute } from '@umbraco-cms/backoffice/resources';
@@ -29,7 +29,7 @@ export class UmbInstallerContext {
 	private _settings = new UmbObjectState<InstallSettingsResponseModel | undefined>(undefined);
 	public readonly settings = this._settings.asObservable();
 
-	private _installStatus = new UmbObjectState<ProblemDetailsModel | null>(null);
+	private _installStatus = new UmbObjectState<ProblemDetails | null>(null);
 	public readonly installStatus = this._installStatus.asObservable();
 
 	constructor() {
@@ -49,10 +49,10 @@ export class UmbInstallerContext {
 	/**
 	 * Observable method to get the install status in the installation process
 	 * @public
-	 * @return {*}  {(Observable<ProblemDetailsModel | null>)}
+	 * @return {*}  {(Observable<ProblemDetails | null>)}
 	 * @memberof UmbInstallerContext
 	 */
-	public installStatusChanges(): Observable<ProblemDetailsModel | null> {
+	public installStatusChanges(): Observable<ProblemDetails | null> {
 		return this.installStatus;
 	}
 
@@ -107,10 +107,10 @@ export class UmbInstallerContext {
 	/**
 	 * Set the install status
 	 * @public
-	 * @param {(ProblemDetailsModel | null)} status
+	 * @param {(ProblemDetails | null)} status
 	 * @memberof UmbInstallerContext
 	 */
-	public setInstallStatus(status: ProblemDetailsModel | null): void {
+	public setInstallStatus(status: ProblemDetails | null): void {
 		this._installStatus.next(status);
 	}
 
diff --git a/src/Umbraco.Web.UI.Client/src/external/backend-api/index.ts b/src/Umbraco.Web.UI.Client/src/external/backend-api/index.ts
index 8420b1093f..4df73b330f 100644
--- a/src/Umbraco.Web.UI.Client/src/external/backend-api/index.ts
+++ b/src/Umbraco.Web.UI.Client/src/external/backend-api/index.ts
@@ -1 +1 @@
-export * from './src';
+export * from './src/index.js';
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/data/data-type.data.ts b/src/Umbraco.Web.UI.Client/src/mocks/data/data-type.data.ts
index e7eb5ba7ea..67a1f1c10a 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/data/data-type.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/data/data-type.data.ts
@@ -691,7 +691,6 @@ class UmbDataTypeData extends UmbEntityData<DataTypeResponseModel | FolderTreeIt
 			name: folder.name,
 			id: folder.id,
 			parentId: folder.parentId,
-			$type: 'FolderTreeItemResponseModel',
 			isFolder: true,
 			isContainer: false,
 		};
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/data/dictionary.data.ts b/src/Umbraco.Web.UI.Client/src/mocks/data/dictionary.data.ts
index d0d45fccbe..72570e8dcd 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/data/dictionary.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/data/dictionary.data.ts
@@ -41,7 +41,6 @@ const dictionaryTree: Array<EntityTreeItemResponseModel> = [
 		hasChildren: true,
 		type: 'dictionary-item',
 		isContainer: false,
-		icon: 'umb:book-alt',
 	},
 	{
 		parentId: 'aae7d0ab-53ba-485d-b8bd-12537f9925cb',
@@ -50,7 +49,6 @@ const dictionaryTree: Array<EntityTreeItemResponseModel> = [
 		hasChildren: false,
 		type: 'dictionary-item',
 		isContainer: false,
-		icon: 'umb:book-alt',
 	},
 ];
 
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/data/document-type.data.ts b/src/Umbraco.Web.UI.Client/src/mocks/data/document-type.data.ts
index db797ad212..3e4cbb3580 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/data/document-type.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/data/document-type.data.ts
@@ -1057,7 +1057,6 @@ export const data: Array<DocumentTypeResponseModel> = [
 
 export const treeData: Array<DocumentTypeTreeItemResponseModel> = [
 	{
-		$type: 'DocumentTypeTreeItemViewModel',
 		name: 'All property editors document type',
 		type: 'document-type',
 		hasChildren: false,
@@ -1067,7 +1066,6 @@ export const treeData: Array<DocumentTypeTreeItemResponseModel> = [
 		icon: '',
 	},
 	{
-		$type: 'DocumentTypeTreeItemViewModel',
 		name: 'Page Document Type',
 		type: 'document-type',
 		hasChildren: false,
@@ -1077,7 +1075,6 @@ export const treeData: Array<DocumentTypeTreeItemResponseModel> = [
 		icon: 'umb:document',
 	},
 	{
-		$type: 'DocumentTypeTreeItemViewModel',
 		name: 'Page Document Type Compositional',
 		type: 'document-type',
 		hasChildren: false,
@@ -1087,7 +1084,6 @@ export const treeData: Array<DocumentTypeTreeItemResponseModel> = [
 		icon: 'umb:document',
 	},
 	{
-		$type: 'DocumentTypeTreeItemViewModel',
 		name: 'Page Document Type Inherited',
 		type: 'document-type',
 		hasChildren: false,
@@ -1097,7 +1093,6 @@ export const treeData: Array<DocumentTypeTreeItemResponseModel> = [
 		icon: 'umb:document',
 	},
 	{
-		$type: 'DocumentTypeTreeItemViewModel',
 		name: 'Simple Document Type',
 		type: 'document-type',
 		hasChildren: false,
@@ -1107,7 +1102,6 @@ export const treeData: Array<DocumentTypeTreeItemResponseModel> = [
 		icon: 'umb:document',
 	},
 	{
-		$type: 'DocumentTypeTreeItemViewModel',
 		name: 'Simple Document Type 2',
 		type: 'document-type',
 		hasChildren: false,
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/data/document.data.ts b/src/Umbraco.Web.UI.Client/src/mocks/data/document.data.ts
index f4ab7b768a..0a3d0fda4c 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/data/document.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/data/document.data.ts
@@ -476,7 +476,6 @@ export const data: Array<DocumentResponseModel> = [
 
 export const treeData: Array<DocumentTreeItemResponseModel> = [
 	{
-		$type: 'DocumentTreeItemViewModel',
 		isProtected: false,
 		isPublished: true,
 		isEdited: false,
@@ -491,7 +490,6 @@ export const treeData: Array<DocumentTreeItemResponseModel> = [
 		hasChildren: false,
 	},
 	{
-		$type: 'DocumentTreeItemViewModel',
 		isProtected: false,
 		isPublished: true,
 		isEdited: false,
@@ -506,7 +504,6 @@ export const treeData: Array<DocumentTreeItemResponseModel> = [
 		hasChildren: true,
 	},
 	{
-		$type: 'DocumentTreeItemViewModel',
 		isProtected: false,
 		isPublished: false,
 		isEdited: false,
@@ -521,7 +518,6 @@ export const treeData: Array<DocumentTreeItemResponseModel> = [
 		hasChildren: false,
 	},
 	{
-		$type: 'DocumentTreeItemViewModel',
 		name: 'Document 5',
 		type: 'document',
 		icon: 'document',
@@ -536,7 +532,6 @@ export const treeData: Array<DocumentTreeItemResponseModel> = [
 		isTrashed: false,
 	},
 	{
-		$type: 'DocumentTreeItemViewModel',
 		name: 'Simple',
 		type: 'document',
 		icon: 'document',
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/data/media-type.data.ts b/src/Umbraco.Web.UI.Client/src/mocks/data/media-type.data.ts
index 93ed60a5ca..4cf1363d3e 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/data/media-type.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/data/media-type.data.ts
@@ -5,7 +5,6 @@ import { FolderTreeItemResponseModel, PagedFolderTreeItemResponseModel } from '@
 
 export const data: Array<MediaTypeDetails> = [
 	{
-		$type: 'media-type',
 		name: 'Media Type 1',
 		type: 'media-type',
 		hasChildren: false,
@@ -13,12 +12,10 @@ export const data: Array<MediaTypeDetails> = [
 		isContainer: false,
 		parentId: null,
 		isFolder: false,
-		icon: '',
 		alias: 'mediaType1',
 		properties: [],
 	},
 	{
-		$type: 'media-type',
 		name: 'Media Type 2',
 		type: 'media-type',
 		hasChildren: false,
@@ -26,7 +23,6 @@ export const data: Array<MediaTypeDetails> = [
 		isContainer: false,
 		parentId: null,
 		isFolder: false,
-		icon: '',
 		alias: 'mediaType2',
 		properties: [],
 	},
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/data/media.data.ts b/src/Umbraco.Web.UI.Client/src/mocks/data/media.data.ts
index 87987c7e3c..b28201d42c 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/data/media.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/data/media.data.ts
@@ -8,7 +8,6 @@ export const data: Array<MediaDetails> = [
 	{
 		name: 'Flipped Car',
 		type: 'media',
-		icon: 'picture',
 		hasChildren: false,
 		id: 'f2f81a40-c989-4b6b-84e2-057cecd3adc1',
 		isContainer: false,
@@ -34,7 +33,6 @@ export const data: Array<MediaDetails> = [
 	{
 		name: 'Umbracoffee',
 		type: 'media',
-		icon: 'picture',
 		hasChildren: false,
 		id: '69431027-8867-45bf-a93b-72bbdabfb177',
 		isContainer: false,
@@ -60,7 +58,6 @@ export const data: Array<MediaDetails> = [
 	{
 		name: 'People',
 		type: 'media',
-		icon: 'folder',
 		hasChildren: true,
 		id: '69461027-8867-45bf-a93b-72bbdabfb177',
 		isContainer: true,
@@ -74,7 +71,6 @@ export const data: Array<MediaDetails> = [
 	{
 		name: 'Products',
 		type: 'media',
-		icon: 'folder',
 		hasChildren: true,
 		id: '69461027-8867-45bf-a93b-5224dabfb177',
 		isContainer: true,
@@ -88,7 +84,6 @@ export const data: Array<MediaDetails> = [
 	{
 		name: 'John Smith',
 		type: 'media',
-		icon: 'picture',
 		hasChildren: false,
 		id: '69431027-8867-45s7-a93b-7uibdabfb177',
 		isContainer: false,
@@ -114,7 +109,6 @@ export const data: Array<MediaDetails> = [
 	{
 		name: 'Jane Doe',
 		type: 'media',
-		icon: 'picture',
 		hasChildren: false,
 		id: '69431027-8867-45s7-a93b-7uibdabf2147',
 		isContainer: false,
@@ -140,7 +134,6 @@ export const data: Array<MediaDetails> = [
 	{
 		name: 'A very nice hat',
 		type: 'media',
-		icon: 'picture',
 		hasChildren: false,
 		id: '694hdj27-8867-45s7-a93b-7uibdabf2147',
 		isContainer: false,
@@ -166,7 +159,6 @@ export const data: Array<MediaDetails> = [
 	{
 		name: 'Fancy old chair',
 		type: 'media',
-		icon: 'picture',
 		hasChildren: false,
 		id: '694hdj27-1237-45s7-a93b-7uibdabfas47',
 		isContainer: false,
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/data/member-group.data.ts b/src/Umbraco.Web.UI.Client/src/mocks/data/member-group.data.ts
index e97b238cd4..f4c4b355a3 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/data/member-group.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/data/member-group.data.ts
@@ -7,7 +7,6 @@ export const data: Array<MemberGroupDetails> = [
 	{
 		name: 'Member Group AAA',
 		type: 'member-group',
-		icon: 'umb:document',
 		hasChildren: false,
 		id: '76708ccd-4179-464c-b694-6969149dd9f9',
 		isContainer: false,
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/data/member-type.data.ts b/src/Umbraco.Web.UI.Client/src/mocks/data/member-type.data.ts
index f8cab90696..ef0843e4c3 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/data/member-type.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/data/member-type.data.ts
@@ -7,7 +7,6 @@ export const data: Array<MemberTypeDetails> = [
 	{
 		name: 'Member Type 1',
 		type: 'member-type',
-		icon: 'icon-user',
 		hasChildren: false,
 		id: 'd59be02f-1df9-4228-aa1e-01917d806cda',
 		isContainer: false,
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/data/member.data.ts b/src/Umbraco.Web.UI.Client/src/mocks/data/member.data.ts
index f2e017fe3f..48eeb82231 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/data/member.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/data/member.data.ts
@@ -10,7 +10,6 @@ export const data: Array<MemberDetails> = [
 	{
 		name: 'Member AAA',
 		type: 'member',
-		icon: 'umb:user',
 		hasChildren: false,
 		id: 'aaa08ccd-4179-464c-b634-6969149dd9f9',
 		isContainer: false,
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/data/partial-views.data.ts b/src/Umbraco.Web.UI.Client/src/mocks/data/partial-views.data.ts
index 003043d9fc..7e98fe19d7 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/data/partial-views.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/data/partial-views.data.ts
@@ -11,7 +11,6 @@ export const data: Array<FileSystemTreeItemPresentationModel> = [
 		isFolder: true,
 		name: 'blockgrid',
 		type: 'partial-view',
-		icon: 'umb:folder',
 		hasChildren: true,
 	},
 	{
@@ -19,7 +18,6 @@ export const data: Array<FileSystemTreeItemPresentationModel> = [
 		isFolder: true,
 		name: 'blocklist',
 		type: 'partial-view',
-		icon: 'umb:folder',
 		hasChildren: true,
 	},
 	{
@@ -27,7 +25,6 @@ export const data: Array<FileSystemTreeItemPresentationModel> = [
 		isFolder: true,
 		name: 'grid',
 		type: 'partial-view',
-		icon: 'umb:folder',
 		hasChildren: true,
 	},
 	{
@@ -35,7 +32,6 @@ export const data: Array<FileSystemTreeItemPresentationModel> = [
 		isFolder: false,
 		name: 'area.cshtml',
 		type: 'partial-view',
-		icon: 'umb:article',
 		hasChildren: false,
 	},
 	{
@@ -43,7 +39,6 @@ export const data: Array<FileSystemTreeItemPresentationModel> = [
 		isFolder: false,
 		name: 'items.cshtml',
 		type: 'partial-view',
-		icon: 'umb:article',
 		hasChildren: false,
 	},
 	{
@@ -51,7 +46,6 @@ export const data: Array<FileSystemTreeItemPresentationModel> = [
 		isFolder: false,
 		name: 'default.cshtml',
 		type: 'partial-view',
-		icon: 'umb:article',
 		hasChildren: false,
 	},
 	{
@@ -59,7 +53,6 @@ export const data: Array<FileSystemTreeItemPresentationModel> = [
 		isFolder: false,
 		name: 'editors',
 		type: 'partial-view',
-		icon: 'umb:folder',
 		hasChildren: false,
 	},
 	{
@@ -67,7 +60,6 @@ export const data: Array<FileSystemTreeItemPresentationModel> = [
 		isFolder: false,
 		name: 'items.cshtml',
 		type: 'partial-view',
-		icon: 'umb:article',
 		hasChildren: false,
 	},
 ];
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/data/relation-type.data.ts b/src/Umbraco.Web.UI.Client/src/mocks/data/relation-type.data.ts
index 73c7061746..8463438cdd 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/data/relation-type.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/data/relation-type.data.ts
@@ -74,47 +74,42 @@ export const data: Array<RelationTypeResponseModel> = [
 export const treeData: Array<EntityTreeItemResponseModel> = [
 	{
 		id: 'e0d39ff5-71d8-453f-b682-9d8d31ee5e06',
-		$type: 'EntityTreeItemViewModel',
+
 		isContainer: false,
 		parentId: null,
 		name: 'Relate Document On Copy',
-		icon: 'umb:trafic',
 		type: 'relation-type',
 	},
 	{
 		id: 'ac68cde6-763f-4231-a751-1101b57defd2',
-		$type: 'EntityTreeItemViewModel',
+
 		isContainer: false,
 		parentId: null,
 		name: 'Relate Parent Document On Delete',
-		icon: 'umb:trafic',
 		type: 'relation-type',
 	},
 	{
 		id: '6f9b800c-762c-42d4-85d9-bf40a77d689e',
-		$type: 'EntityTreeItemViewModel',
+
 		isContainer: false,
 		parentId: null,
 		name: 'Relate Parent Media Folder On Delete',
-		icon: 'umb:trafic',
 		type: 'relation-type',
 	},
 	{
 		id: 'd421727d-43de-4205-b4c6-037404f309ad',
-		$type: 'EntityTreeItemViewModel',
+
 		isContainer: false,
 		parentId: null,
 		name: 'Related Media',
-		icon: 'umb:trafic',
 		type: 'relation-type',
 	},
 	{
 		id: 'e9a0a28e-2d5b-4229-ac00-66f2df230513',
-		$type: 'EntityTreeItemViewModel',
+
 		isContainer: false,
 		parentId: null,
 		name: 'Related Document',
-		icon: 'umb:trafic',
 		type: 'relation-type',
 	},
 ];
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/data/stylesheet.data.ts b/src/Umbraco.Web.UI.Client/src/mocks/data/stylesheet.data.ts
index aa66e2935a..05548ef529 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/data/stylesheet.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/data/stylesheet.data.ts
@@ -15,7 +15,6 @@ export const data: Array<StylesheetDBItem> = [
 		isFolder: false,
 		name: 'Stylesheet File 1.css',
 		type: 'stylesheet',
-		icon: 'umb:brackets',
 		hasChildren: false,
 		content: `Stylesheet content 1`,
 	},
@@ -24,7 +23,6 @@ export const data: Array<StylesheetDBItem> = [
 		isFolder: false,
 		name: 'Stylesheet File 2.css',
 		type: 'stylesheet',
-		icon: 'umb:brackets',
 		hasChildren: false,
 		content: `Stylesheet content 2`,
 	},
@@ -33,7 +31,6 @@ export const data: Array<StylesheetDBItem> = [
 		isFolder: true,
 		name: 'Folder 1',
 		type: 'stylesheet',
-		icon: 'umb:folder',
 		hasChildren: true,
 		content: `Stylesheet content 3`,
 	},
@@ -42,7 +39,6 @@ export const data: Array<StylesheetDBItem> = [
 		isFolder: false,
 		name: 'Stylesheet File 3.css',
 		type: 'stylesheet',
-		icon: 'umb:brackets',
 		hasChildren: false,
 		content: `Stylesheet content 3`,
 	},
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/data/template.data.ts b/src/Umbraco.Web.UI.Client/src/mocks/data/template.data.ts
index 9bfc263044..3f86982c48 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/data/template.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/data/template.data.ts
@@ -39,7 +39,6 @@ export const data: Array<TemplateDBItem> = [
 		parentId: null,
 		name: 'Doc 1',
 		type: 'template',
-		icon: 'umb:layout',
 		hasChildren: false,
 		alias: 'Doc1',
 		content: `@using Umbraco.Extensions
@@ -62,7 +61,6 @@ export const data: Array<TemplateDBItem> = [
 		parentId: null,
 		name: 'Test',
 		type: 'template',
-		icon: 'umb:layout',
 		hasChildren: true,
 		alias: 'Test',
 		content:
@@ -75,7 +73,6 @@ export const data: Array<TemplateDBItem> = [
 		masterTemplateId: '9a84c0b3-03b4-4dd4-84ac-706740ac0f71',
 		name: 'Child',
 		type: 'template',
-		icon: 'umb:layout',
 		hasChildren: false,
 		alias: 'Test',
 		content:
@@ -88,7 +85,6 @@ export const data: Array<TemplateDBItem> = [
 		name: 'Has Master Template',
 		masterTemplateId: '9a84c0b3-03b4-4dd4-84ac-706740ac0f71',
 		type: 'template',
-		icon: 'umb:layout',
 		hasChildren: false,
 		alias: 'hasMasterTemplate',
 		content:
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/data/user-groups.data.ts b/src/Umbraco.Web.UI.Client/src/mocks/data/user-groups.data.ts
index 0ec4dbad02..968fb0919d 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/data/user-groups.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/data/user-groups.data.ts
@@ -17,7 +17,6 @@ class UmbUserGroupsData extends UmbEntityData<UserGroupResponseModel> {
 
 export const data: Array<UserGroupResponseModel> = [
 	{
-		$type: 'UserGroupResponseModel',
 		id: 'c630d49e-4e7b-42ea-b2bc-edc0edacb6b1',
 		name: 'Administrators',
 		icon: 'umb:medal',
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/data/users.data.ts b/src/Umbraco.Web.UI.Client/src/mocks/data/users.data.ts
index dadb4faae1..c3ace50024 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/data/users.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/data/users.data.ts
@@ -23,7 +23,6 @@ class UmbUsersData extends UmbData<UserResponseModel> {
 		const firstUser = this.data[0];
 
 		return {
-			$type: 'CurrentUserResponseModel',
 			id: firstUser.id,
 			name: firstUser.name,
 			email: firstUser.email,
@@ -113,7 +112,6 @@ export const data: Array<UserResponseModel & { type: string }> = [
 	{
 		id: 'bca6c733-a63d-4353-a271-9a8b6bcca8bd',
 		type: 'user',
-		$type: 'UserResponseModel',
 		contentStartNodeIds: [],
 		mediaStartNodeIds: [],
 		name: 'Umbraco User',
@@ -131,7 +129,6 @@ export const data: Array<UserResponseModel & { type: string }> = [
 	{
 		id: '82e11d3d-b91d-43c9-9071-34d28e62e81d',
 		type: 'user',
-		$type: 'UserResponseModel',
 		contentStartNodeIds: [],
 		mediaStartNodeIds: [],
 		name: 'Amelie Walker',
@@ -149,7 +146,6 @@ export const data: Array<UserResponseModel & { type: string }> = [
 	{
 		id: 'aa1d83a9-bc7f-47d2-b288-58d8a31f5017',
 		type: 'user',
-		$type: 'UserResponseModel',
 		contentStartNodeIds: [],
 		mediaStartNodeIds: [],
 		name: 'Oliver Kim',
@@ -167,7 +163,6 @@ export const data: Array<UserResponseModel & { type: string }> = [
 	{
 		id: 'ff2f4a50-d3d4-4bc4-869d-c7948c160e54',
 		type: 'user',
-		$type: 'UserResponseModel',
 		contentStartNodeIds: [],
 		mediaStartNodeIds: [],
 		name: 'Eliana Nieves',
@@ -185,7 +180,6 @@ export const data: Array<UserResponseModel & { type: string }> = [
 	{
 		id: 'c290c6d9-9f12-4838-8567-621b52a178de',
 		type: 'user',
-		$type: 'UserResponseModel',
 		contentStartNodeIds: [],
 		mediaStartNodeIds: [],
 		name: 'Jasmine Patel',
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/data/utils.ts b/src/Umbraco.Web.UI.Client/src/mocks/data/utils.ts
index 3bea1d8168..272efad196 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/data/utils.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/data/utils.ts
@@ -13,7 +13,6 @@ export const createEntityTreeItem = (item: any): EntityTreeItemResponseModel =>
 	return {
 		name: item.name,
 		type: item.type,
-		icon: item.icon,
 		hasChildren: item.hasChildren,
 		id: item.id,
 		isContainer: item.isContainer,
@@ -24,7 +23,6 @@ export const createEntityTreeItem = (item: any): EntityTreeItemResponseModel =>
 export const createFolderTreeItem = (item: any): FolderTreeItemResponseModel => {
 	return {
 		...createEntityTreeItem(item),
-		$type: 'FolderTreeItemResponseModel',
 		isFolder: item.isFolder,
 	};
 };
@@ -45,7 +43,6 @@ export const createDocumentTreeItem = (
 ): DocumentTreeItemResponseModel & { isTrashed: boolean } => {
 	return {
 		...createContentTreeItem(item),
-		$type: 'DocumentTreeItemViewModel',
 		type: 'document',
 		icon: 'document', // TODO: Should get this from document type...
 		name: item.variants?.[0].name ?? '',
@@ -71,7 +68,6 @@ export const createFileSystemTreeItem = (item: any): FileSystemTreeItemPresentat
 	return {
 		name: item.name,
 		type: item.type,
-		icon: item.icon,
 		hasChildren: item.hasChildren,
 		path: item.path,
 		isFolder: item.isFolder,
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/handlers/data-type/folder.handlers.ts b/src/Umbraco.Web.UI.Client/src/mocks/handlers/data-type/folder.handlers.ts
index f59c6f30ab..dbf40c4849 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/handlers/data-type/folder.handlers.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/handlers/data-type/folder.handlers.ts
@@ -2,7 +2,7 @@ const { rest } = window.MockServiceWorker;
 import { umbDataTypeData } from '../../data/data-type.data.js';
 import { slug } from './slug.js';
 import { umbracoPath } from '@umbraco-cms/backoffice/utils';
-import { ProblemDetailsModel } from '@umbraco-cms/backoffice/backend-api';
+import { ProblemDetails } from '@umbraco-cms/backoffice/backend-api';
 
 export const folderHandlers = [
 	rest.post(umbracoPath(`${slug}/folder`), async (req, res, ctx) => {
@@ -44,7 +44,7 @@ export const folderHandlers = [
 		} catch (error) {
 			return res(
 				ctx.status(404),
-				ctx.json<ProblemDetailsModel>({
+				ctx.json<ProblemDetails>({
 					status: 404,
 					type: 'error',
 					detail: 'Not Found',
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/handlers/dictionary.handlers.ts b/src/Umbraco.Web.UI.Client/src/mocks/handlers/dictionary.handlers.ts
index a720b0a7b7..874bb40a16 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/handlers/dictionary.handlers.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/handlers/dictionary.handlers.ts
@@ -20,7 +20,6 @@ const importResponse: DictionaryItemResponseModel & EntityTreeItemResponseModel
 	hasChildren: false,
 	type: 'dictionary-item',
 	isContainer: false,
-	icon: 'umb:book-alt',
 	translations: [
 		{
 			isoCode: 'en',
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/handlers/install.handlers.ts b/src/Umbraco.Web.UI.Client/src/mocks/handlers/install.handlers.ts
index 5edcd01462..7d36eaf4fc 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/handlers/install.handlers.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/handlers/install.handlers.ts
@@ -3,7 +3,7 @@ import {
 	DatabaseInstallResponseModel,
 	InstallVResponseModel,
 	InstallSettingsResponseModel,
-	ProblemDetailsModel,
+	ProblemDetails,
 	TelemetryLevelModel,
 } from '@umbraco-cms/backoffice/backend-api';
 import { umbracoPath } from '@umbraco-cms/backoffice/utils';
@@ -84,7 +84,7 @@ export const handlers = [
 		if (body.name === 'validate') {
 			return res(
 				ctx.status(400),
-				ctx.json<ProblemDetailsModel>({
+				ctx.json<ProblemDetails>({
 					type: 'connection',
 					status: 400,
 					detail: 'Database connection failed',
@@ -106,7 +106,7 @@ export const handlers = [
 				// Respond with a 200 status code
 				ctx.status(400),
 				ctx.delay(1000),
-				ctx.json<ProblemDetailsModel>({
+				ctx.json<ProblemDetails>({
 					type: 'validation',
 					status: 400,
 					detail: 'Something went wrong',
diff --git a/src/Umbraco.Web.UI.Client/src/mocks/handlers/language.handlers.ts b/src/Umbraco.Web.UI.Client/src/mocks/handlers/language.handlers.ts
index 86cefc4af3..0ac0d51b67 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/handlers/language.handlers.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/handlers/language.handlers.ts
@@ -1,6 +1,6 @@
 const { rest } = window.MockServiceWorker;
 import { umbLanguagesData } from '../data/languages.data.js';
-import { LanguageResponseModel, ProblemDetailsModel } from '@umbraco-cms/backoffice/backend-api';
+import { LanguageResponseModel, ProblemDetails } from '@umbraco-cms/backoffice/backend-api';
 import { umbracoPath } from '@umbraco-cms/backoffice/utils';
 
 // TODO: add schema
@@ -48,7 +48,7 @@ export const handlers = [
 		} catch (error) {
 			return res(
 				ctx.status(400),
-				ctx.json<ProblemDetailsModel>({
+				ctx.json<ProblemDetails>({
 					status: 400,
 					type: 'validation',
 					detail: 'Something went wrong',
diff --git a/src/Umbraco.Web.UI.Client/src/packages/core/modal/common/folder/folder-modal.element.ts b/src/Umbraco.Web.UI.Client/src/packages/core/modal/common/folder/folder-modal.element.ts
index 5e2fdeb512..4f329a9def 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/core/modal/common/folder/folder-modal.element.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/core/modal/common/folder/folder-modal.element.ts
@@ -4,7 +4,7 @@ import { UmbFolderModalData, UmbFolderModalResult, UmbModalContext } from '@umbr
 import { UmbLitElement } from '@umbraco-cms/internal/lit-element';
 import { UmbFolderRepository } from '@umbraco-cms/backoffice/repository';
 import { createExtensionClass, ManifestBase } from '@umbraco-cms/backoffice/extension-api';
-import { FolderReponseModel, ProblemDetailsModel } from '@umbraco-cms/backoffice/backend-api';
+import { FolderReponseModel, ProblemDetails } from '@umbraco-cms/backoffice/backend-api';
 import { UmbObserverController } from '@umbraco-cms/backoffice/observable-api';
 import { umbExtensionsRegistry } from '@umbraco-cms/backoffice/extension-registry';
 
@@ -102,7 +102,7 @@ export class UmbFolderModalElement extends UmbLitElement {
 		const isValid = this._formElement?.checkValidity();
 		if (!isValid) return;
 
-		let error: ProblemDetailsModel | undefined;
+		let error: ProblemDetails | undefined;
 
 		const formData = new FormData(this._formElement);
 		const folderName = formData.get('name') as string;
diff --git a/src/Umbraco.Web.UI.Client/src/packages/core/tree/tree-item/tree-item.context.interface.ts b/src/Umbraco.Web.UI.Client/src/packages/core/tree/tree-item/tree-item.context.interface.ts
index 2d208cf3cf..c03290698a 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/core/tree/tree-item/tree-item.context.interface.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/core/tree/tree-item/tree-item.context.interface.ts
@@ -1,6 +1,6 @@
 import type { Observable } from '@umbraco-cms/backoffice/external/rxjs';
 import type { UmbControllerHostElement } from '@umbraco-cms/backoffice/controller-api';
-import type { ProblemDetailsModel, TreeItemPresentationModel } from '@umbraco-cms/backoffice/backend-api';
+import type { ProblemDetails, TreeItemPresentationModel } from '@umbraco-cms/backoffice/backend-api';
 import { UmbPagedData } from '@umbraco-cms/backoffice/repository';
 
 export interface UmbTreeItemContext<TreeItemType extends TreeItemPresentationModel> {
@@ -20,7 +20,7 @@ export interface UmbTreeItemContext<TreeItemType extends TreeItemPresentationMod
 	setTreeItem(treeItem: TreeItemType | undefined): void;
 	requestChildren(): Promise<{
 		data?: UmbPagedData<TreeItemType> | undefined;
-		error?: ProblemDetailsModel | undefined;
+		error?: ProblemDetails | undefined;
 		asObservable?: () => Observable<TreeItemType[]>;
 	}>;
 	toggleContextMenu(): void;
diff --git a/src/Umbraco.Web.UI.Client/src/packages/core/tree/tree.context.ts b/src/Umbraco.Web.UI.Client/src/packages/core/tree/tree.context.ts
index 05fb106310..ef94d2f024 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/core/tree/tree.context.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/core/tree/tree.context.ts
@@ -4,7 +4,7 @@ import { ManifestTree, umbExtensionsRegistry } from '@umbraco-cms/backoffice/ext
 import { UmbBooleanState } from '@umbraco-cms/backoffice/observable-api';
 import { UmbBaseController, UmbControllerHostElement } from '@umbraco-cms/backoffice/controller-api';
 import { createExtensionClass } from '@umbraco-cms/backoffice/extension-api';
-import { ProblemDetailsModel, TreeItemPresentationModel } from '@umbraco-cms/backoffice/backend-api';
+import { ProblemDetails, TreeItemPresentationModel } from '@umbraco-cms/backoffice/backend-api';
 import { UmbContextProviderController } from '@umbraco-cms/backoffice/context-api';
 import { UmbSelectionManagerBase } from '@umbraco-cms/backoffice/utils';
 
@@ -22,7 +22,7 @@ export interface UmbTreeContext<TreeItemType extends TreeItemPresentationModel>
 	deselect(unique: string | null): void;
 	requestChildrenOf: (parentUnique: string | null) => Promise<{
 		data?: UmbPagedData<TreeItemType>;
-		error?: ProblemDetailsModel;
+		error?: ProblemDetails;
 		asObservable?: () => Observable<TreeItemType[]>;
 	}>;
 }
diff --git a/src/Umbraco.Web.UI.Client/src/packages/documents/document-types/modals/allowed-document-types/allowed-document-types-modal.element.ts b/src/Umbraco.Web.UI.Client/src/packages/documents/document-types/modals/allowed-document-types/allowed-document-types-modal.element.ts
index 08e918d046..4aad7b6baa 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/documents/document-types/modals/allowed-document-types/allowed-document-types-modal.element.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/documents/document-types/modals/allowed-document-types/allowed-document-types-modal.element.ts
@@ -51,7 +51,7 @@ export class UmbAllowedDocumentTypesModalElement extends UmbModalBaseElement<
 		const { data } = await this.#documentTypeRepository.requestRootTreeItems();
 		if (!data) return;
 
-		const allFullModels: Array<DocumentTypeResponseModel & { $type: '' }> = [];
+		const allFullModels: Array<DocumentTypeResponseModel> = [];
 		await Promise.all(
 			data.items.map((item) => {
 				if (item.id) {
@@ -83,7 +83,7 @@ export class UmbAllowedDocumentTypesModalElement extends UmbModalBaseElement<
 
 	render() {
 		return html`
-			<umb-body-layout headline=${this._headline}>
+			<umb-body-layout headline=${this._headline ?? ''}>
 				<uui-box>
 					${this._allowedDocumentTypes.length === 0 ? html`<p>No allowed types</p>` : nothing}
 					${this._allowedDocumentTypes.map(
diff --git a/src/Umbraco.Web.UI.Client/src/packages/documents/document-types/repository/document-type.repository.ts b/src/Umbraco.Web.UI.Client/src/packages/documents/document-types/repository/document-type.repository.ts
index b4a4954507..52234e5c7f 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/documents/document-types/repository/document-type.repository.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/documents/document-types/repository/document-type.repository.ts
@@ -14,7 +14,7 @@ import {
 } from '@umbraco-cms/backoffice/backend-api';
 import { UmbNotificationContext, UMB_NOTIFICATION_CONTEXT_TOKEN } from '@umbraco-cms/backoffice/notification';
 
-type ItemType = DocumentTypeResponseModel & { $type: string };
+type ItemType = DocumentTypeResponseModel;
 
 export class UmbDocumentTypeRepository
 	implements
@@ -181,7 +181,7 @@ export class UmbDocumentTypeRepository
 
 			// Temporary hack while we are not in control of IDs:
 
-			const newDocument = { ...(await this.requestById(newId)).data, $type: '' };
+			const newDocument = { ...(await this.requestById(newId)).data };
 
 			if (newDocument) {
 				const notification = { data: { message: `Document Type created` } };
@@ -255,7 +255,6 @@ export const createTreeItem = (item: ItemType): FolderTreeItemResponseModel => {
 
 	// TODO: needs parentID, this is missing in the current model. Should be good when updated to a createModel.
 	return {
-		$type: 'FolderTreeItemResponseModel',
 		type: 'document-type',
 		parentId: null,
 		name: item.name,
diff --git a/src/Umbraco.Web.UI.Client/src/packages/documents/document-types/repository/sources/document-type.server.data.ts b/src/Umbraco.Web.UI.Client/src/packages/documents/document-types/repository/sources/document-type.server.data.ts
index fae6d284af..492fb7fec9 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/documents/document-types/repository/sources/document-type.server.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/documents/document-types/repository/sources/document-type.server.data.ts
@@ -56,10 +56,8 @@ export class UmbDocumentTypeServerDataSource
 	 * @memberof UmbDocumentTypeServerDataSource
 	 */
 	async createScaffold(parentId: string | null) {
-		// TODO: Type hack to append $type and parentId to the DocumentTypeResponseModel.
 		//, parentId: string | null
-		const data: DocumentTypeResponseModel & { $type: string } = {
-			$type: 'string',
+		const data: DocumentTypeResponseModel = {
 			id: UmbId.new(),
 			//parentId: parentId,
 			name: '',
@@ -99,7 +97,6 @@ export class UmbDocumentTypeServerDataSource
 		documentType = { ...documentType };
 
 		// TODO: Hack to remove some props that ruins the document-type post end-point.
-		(documentType as any).$type = undefined;
 		(documentType as any).id = undefined;
 
 		// TODO: Investigate if this matters (should go away anyway when we have the end-point accepts us defining the ids.)
@@ -131,7 +128,6 @@ export class UmbDocumentTypeServerDataSource
 		documentType = { ...documentType };
 
 		// TODO: Hack to remove some props that ruins the document-type post end-point.
-		(documentType as any).$type = undefined;
 		(documentType as any).id = undefined;
 
 		return tryExecuteAndNotify(this.#host, DocumentTypeResource.putDocumentTypeById({ id, requestBody: documentType }));
diff --git a/src/Umbraco.Web.UI.Client/src/packages/documents/documents/collection/views/table/document-table-collection-view.element.ts b/src/Umbraco.Web.UI.Client/src/packages/documents/documents/collection/views/table/document-table-collection-view.element.ts
index aa87997ff4..8dec27dc4d 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/documents/documents/collection/views/table/document-table-collection-view.element.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/documents/documents/collection/views/table/document-table-collection-view.element.ts
@@ -79,7 +79,6 @@ export class UmbDocumentTableCollectionViewElement extends UmbLitElement {
 			if (!item.id) throw new Error('Item id is missing.');
 			return {
 				id: item.id,
-				icon: item.icon,
 				data: [
 					{
 						columnAlias: 'entityName',
diff --git a/src/Umbraco.Web.UI.Client/src/packages/documents/documents/repository/sources/document.server.data.ts b/src/Umbraco.Web.UI.Client/src/packages/documents/documents/repository/sources/document.server.data.ts
index 71b0024cd2..777fff649f 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/documents/documents/repository/sources/document.server.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/documents/documents/repository/sources/document.server.data.ts
@@ -65,7 +65,6 @@ export class UmbDocumentServerDataSource
 			values: [],
 			variants: [
 				{
-					$type: 'DocumentVariantRequestModel',
 					state: ContentStateModel.DRAFT,
 					publishDate: null,
 					culture: null,
@@ -92,12 +91,11 @@ export class UmbDocumentServerDataSource
 
 		// TODO: Hack to remove some props that ruins the document-type post end-point.
 		const unFroozenDocument = { ...document };
-		(unFroozenDocument as any).$type = undefined;
 		(unFroozenDocument as any).id = undefined;
 
 		(unFroozenDocument.variants as any) =
 			unFroozenDocument.variants?.map((variant) => {
-				return { ...variant, $type: undefined };
+				return { ...variant };
 			}) ?? [];
 
 		return tryExecuteAndNotify(this.#host, DocumentResource.postDocument({ requestBody: unFroozenDocument }));
@@ -114,12 +112,11 @@ export class UmbDocumentServerDataSource
 
 		// TODO: Hack to remove some props that ruins the document-type post end-point.
 		const unFroozenDocument = { ...document };
-		(unFroozenDocument as any).$type = undefined;
 		(unFroozenDocument as any).id = undefined;
 
 		(unFroozenDocument.variants as any) =
 			unFroozenDocument.variants?.map((variant) => {
-				return { ...variant, $type: undefined };
+				return { ...variant };
 			}) ?? [];
 
 		return tryExecuteAndNotify(this.#host, DocumentResource.putDocumentById({ id, requestBody: unFroozenDocument }));
diff --git a/src/Umbraco.Web.UI.Client/src/packages/documents/documents/workspace/document-workspace.context.ts b/src/Umbraco.Web.UI.Client/src/packages/documents/documents/workspace/document-workspace.context.ts
index cf1096d0e1..98d18c9624 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/documents/documents/workspace/document-workspace.context.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/documents/documents/workspace/document-workspace.context.ts
@@ -152,7 +152,7 @@ export class UmbDocumentWorkspaceContext
 		}
 	}
 	setPropertyValue(alias: string, value: unknown, variantId?: UmbVariantId) {
-		const entry = { $type: 'DocumentValueModel', ...variantId?.toObject(), alias, value };
+		const entry = { ...variantId?.toObject(), alias, value };
 		const currentData = this.#draft.value;
 		if (currentData) {
 			const values = appendToFrozenArray(
diff --git a/src/Umbraco.Web.UI.Client/src/packages/media/media/collection-view/media-table-collection-view.element.ts b/src/Umbraco.Web.UI.Client/src/packages/media/media/collection-view/media-table-collection-view.element.ts
index d2b890631c..ee3881bf61 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/media/media/collection-view/media-table-collection-view.element.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/media/media/collection-view/media-table-collection-view.element.ts
@@ -67,7 +67,6 @@ export class UmbMediaTableCollectionViewElement extends UmbLitElement {
 		this._tableItems = mediaItems.map((item) => {
 			return {
 				id: item.id,
-				icon: item.icon,
 				data: [
 					{
 						columnAlias: 'mediaName',
diff --git a/src/Umbraco.Web.UI.Client/src/packages/members/members/repository/sources/member.tree.server.data.ts b/src/Umbraco.Web.UI.Client/src/packages/members/members/repository/sources/member.tree.server.data.ts
index 8348c70143..dbe714abc5 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/members/members/repository/sources/member.tree.server.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/members/members/repository/sources/member.tree.server.data.ts
@@ -45,7 +45,7 @@ export class UmbMemberTreeServerDataSource implements MemberTreeDataSource {
 		return { data, error: undefined };
 
 		// if (ids) {
-		// 	const error: ProblemDetailsModel = { title: 'Ids are missing' };
+		// 	const error: ProblemDetails = { title: 'Ids are missing' };
 		// 	return { error };
 		// }
 
diff --git a/src/Umbraco.Web.UI.Client/src/packages/settings/data-types/models.ts b/src/Umbraco.Web.UI.Client/src/packages/settings/data-types/models.ts
index 33e35d560d..a21244deba 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/settings/data-types/models.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/settings/data-types/models.ts
@@ -1,5 +1,5 @@
 import { DataTypeResponseModel } from '@umbraco-cms/backoffice/backend-api';
 
-export interface UmbDataTypeModel extends Omit<DataTypeResponseModel, '$type'> {
+export interface UmbDataTypeModel extends DataTypeResponseModel {
 	type: 'data-type' | 'data-type-folder' | 'data-type-root';
 }
diff --git a/src/Umbraco.Web.UI.Client/src/packages/settings/data-types/repository/data-type.repository.ts b/src/Umbraco.Web.UI.Client/src/packages/settings/data-types/repository/data-type.repository.ts
index 9fcad97e91..498e2ba81b 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/settings/data-types/repository/data-type.repository.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/settings/data-types/repository/data-type.repository.ts
@@ -365,7 +365,6 @@ export const createTreeItem = (item: CreateDataTypeRequestModel): FolderTreeItem
 	if (!item.id) throw new Error('item.id is null or undefined');
 
 	return {
-		$type: 'FolderTreeItemResponseModel',
 		type: 'data-type',
 		parentId: item.parentId,
 		name: item.name,
diff --git a/src/Umbraco.Web.UI.Client/src/packages/settings/data-types/repository/sources/data-type-folder.server.data.ts b/src/Umbraco.Web.UI.Client/src/packages/settings/data-types/repository/sources/data-type-folder.server.data.ts
index a6258bec44..04c7e0223b 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/settings/data-types/repository/sources/data-type-folder.server.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/settings/data-types/repository/sources/data-type-folder.server.data.ts
@@ -35,7 +35,6 @@ export class UmbDataTypeFolderServerDataSource implements UmbFolderDataSource {
 	 */
 	async createScaffold(parentId: string | null) {
 		const scaffold: FolderReponseModel = {
-			$type: 'FolderReponseModel',
 			name: '',
 			id: UmbId.new(),
 			parentId,
diff --git a/src/Umbraco.Web.UI.Client/src/packages/templating/code-editor/code-editor.stories.ts b/src/Umbraco.Web.UI.Client/src/packages/templating/code-editor/code-editor.stories.ts
index f857399c2a..655c8cb844 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/templating/code-editor/code-editor.stories.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/templating/code-editor/code-editor.stories.ts
@@ -132,11 +132,11 @@ const codeSnippets: Record<CodeEditorLanguage, string> = {
 		}
 
 		setName(value: string) {
-			this.#data.next({ ...this.#data.value, $type: this.#data.value?.$type || '', name: value });
+			this.#data.next({ ...this.#data.value, name: value });
 		}
 
 		setContent(value: string) {
-			this.#data.next({ ...this.#data.value, $type: this.#data.value?.$type || '', content: value });
+			this.#data.next({ ...this.#data.value, content: value });
 		}
 
 		async load(entityId: string) {
diff --git a/src/Umbraco.Web.UI.Client/src/packages/templating/partial-views/repository/partial-views.repository.ts b/src/Umbraco.Web.UI.Client/src/packages/templating/partial-views/repository/partial-views.repository.ts
index dd11f0140c..ba053e001f 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/templating/partial-views/repository/partial-views.repository.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/templating/partial-views/repository/partial-views.repository.ts
@@ -4,7 +4,7 @@ import { UmbPartialViewsTreeStore, UMB_PARTIAL_VIEW_TREE_STORE_CONTEXT_TOKEN } f
 import { Observable } from '@umbraco-cms/backoffice/external/rxjs';
 import { UmbControllerHostElement } from '@umbraco-cms/backoffice/controller-api';
 import { UmbContextConsumerController } from '@umbraco-cms/backoffice/context-api';
-import { ProblemDetailsModel } from '@umbraco-cms/backoffice/backend-api';
+import { ProblemDetails } from '@umbraco-cms/backoffice/backend-api';
 import { UmbDetailRepository, UmbTreeRepository } from '@umbraco-cms/backoffice/repository';
 import { UmbTreeRootEntityModel } from '@umbraco-cms/backoffice/tree';
 
@@ -30,7 +30,7 @@ export class UmbTemplateRepository implements UmbTreeRepository<any>, UmbDetailR
 		]);
 	}
 
-	requestTreeRoot(): Promise<{ data?: UmbTreeRootEntityModel | undefined; error?: ProblemDetailsModel | undefined }> {
+	requestTreeRoot(): Promise<{ data?: UmbTreeRootEntityModel | undefined; error?: ProblemDetails | undefined }> {
 		//throw new Error('Method not implemented.');
 		return { data: undefined, error: undefined } as any;
 	}
@@ -38,7 +38,7 @@ export class UmbTemplateRepository implements UmbTreeRepository<any>, UmbDetailR
 	requestItemsLegacy?:
 		| ((uniques: string[]) => Promise<{
 				data?: any[] | undefined;
-				error?: ProblemDetailsModel | undefined;
+				error?: ProblemDetails | undefined;
 				asObservable?: (() => Observable<any[]>) | undefined;
 		  }>)
 		| undefined;
@@ -52,7 +52,7 @@ export class UmbTemplateRepository implements UmbTreeRepository<any>, UmbDetailR
 	// TODO: This method to be done, or able to go away?
 	// eslint-disable-next-line @typescript-eslint/ban-ts-comment
 	// @ts-ignore
-	requestById(id: string): Promise<{ data?: any; error?: ProblemDetailsModel | undefined }> {
+	requestById(id: string): Promise<{ data?: any; error?: ProblemDetails | undefined }> {
 		throw new Error('Method not implemented.');
 	}
 
@@ -88,7 +88,7 @@ export class UmbTemplateRepository implements UmbTreeRepository<any>, UmbDetailR
 		await this.#init;
 
 		if (!keys) {
-			const error: ProblemDetailsModel = { title: 'Keys are missing' };
+			const error: ProblemDetails = { title: 'Keys are missing' };
 			return { data: undefined, error };
 		}
 
diff --git a/src/Umbraco.Web.UI.Client/src/packages/templating/partial-views/repository/sources/partial-views.tree.server.data.ts b/src/Umbraco.Web.UI.Client/src/packages/templating/partial-views/repository/sources/partial-views.tree.server.data.ts
index 9abb91e1b0..619f372a74 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/templating/partial-views/repository/sources/partial-views.tree.server.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/templating/partial-views/repository/sources/partial-views.tree.server.data.ts
@@ -1,5 +1,5 @@
 import { PartialViewsTreeDataSource } from './index.js';
-import { PartialViewResource, ProblemDetailsModel } from '@umbraco-cms/backoffice/backend-api';
+import { PartialViewResource, ProblemDetails } from '@umbraco-cms/backoffice/backend-api';
 import { UmbControllerHostElement } from '@umbraco-cms/backoffice/controller-api';
 import { tryExecuteAndNotify } from '@umbraco-cms/backoffice/resources';
 
@@ -24,7 +24,7 @@ export class UmbPartialViewsTreeServerDataSource implements PartialViewsTreeData
 		take?: number | undefined;
 	}) {
 		if (!path) {
-			const error: ProblemDetailsModel = { title: 'Path is missing' };
+			const error: ProblemDetails = { title: 'Path is missing' };
 			return error;
 		}
 
@@ -40,7 +40,7 @@ export class UmbPartialViewsTreeServerDataSource implements PartialViewsTreeData
 
 	async getItem(id: Array<string>) {
 		if (!id) {
-			const error: ProblemDetailsModel = { title: 'Paths are missing' };
+			const error: ProblemDetails = { title: 'Paths are missing' };
 			return error;
 		}
 
diff --git a/src/Umbraco.Web.UI.Client/src/packages/templating/partial-views/workspace/partial-views-workspace.context.ts b/src/Umbraco.Web.UI.Client/src/packages/templating/partial-views/workspace/partial-views-workspace.context.ts
index 6ccc43c323..94e1fd891b 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/templating/partial-views/workspace/partial-views-workspace.context.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/templating/partial-views/workspace/partial-views-workspace.context.ts
@@ -31,11 +31,11 @@ export class UmbPartialViewsWorkspaceContext extends UmbWorkspaceContext<UmbTemp
 	}
 
 	setName(value: string) {
-		this.#data.next({ ...this.#data.value, $type: this.#data.value?.$type || '', name: value });
+		this.#data.next({ ...this.#data.value, name: value });
 	}
 
 	setContent(value: string) {
-		this.#data.next({ ...this.#data.value, $type: this.#data.value?.$type || '', content: value });
+		this.#data.next({ ...this.#data.value, content: value });
 	}
 
 	async load(entityKey: string) {
diff --git a/src/Umbraco.Web.UI.Client/src/packages/templating/templates/repository/template.repository.ts b/src/Umbraco.Web.UI.Client/src/packages/templating/templates/repository/template.repository.ts
index 46e157024a..ed33455259 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/templating/templates/repository/template.repository.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/templating/templates/repository/template.repository.ts
@@ -188,7 +188,7 @@ export class UmbTemplateRepository
 
 		// TODO: we currently don't use the detail store for anything.
 		// Consider to look up the data before fetching from the server
-		//this.#store?.append({ ...template, $type: 'EntityTreeItemResponseModel' });
+		//this.#store?.append({ ...template });
 		// TODO: Update tree store with the new item? or ask tree to request the new item?
 
 		return { error };
diff --git a/src/Umbraco.Web.UI.Client/src/packages/templating/templates/workspace/template-workspace.context.ts b/src/Umbraco.Web.UI.Client/src/packages/templating/templates/workspace/template-workspace.context.ts
index 6f0f55799a..d90354675a 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/templating/templates/workspace/template-workspace.context.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/templating/templates/workspace/template-workspace.context.ts
@@ -51,15 +51,15 @@ export class UmbTemplateWorkspaceContext extends UmbWorkspaceContext<UmbTemplate
 	}
 
 	setName(value: string) {
-		this.#data.next({ ...this.#data.value, $type: this.#data.value?.$type || '', name: value });
+		this.#data.next({ ...this.#data.value, name: value });
 	}
 
 	setAlias(value: string) {
-		this.#data.next({ ...this.#data.value, $type: this.#data.value?.$type || '', alias: value });
+		this.#data.next({ ...this.#data.value, alias: value });
 	}
 
 	setContent(value: string) {
-		this.#data.next({ ...this.#data.value, $type: this.#data.value?.$type || '', content: value });
+		this.#data.next({ ...this.#data.value, content: value });
 	}
 
 	getLayoutBlockRegexPattern() {
@@ -156,7 +156,7 @@ ${currentContent}`;
 		const { data } = await this.repository.createScaffold(parentId);
 		if (!data) return;
 		this.setIsNew(true);
-		this.#data.next({ ...data, id: '', name: '', alias: '', $type: 'TemplateResponseModel' });
+		this.#data.next({ ...data, id: '', name: '', alias: '' });
 		if (!parentId) return;
 		await this.setMasterTemplate(parentId);
 	}
diff --git a/src/Umbraco.Web.UI.Client/src/packages/translation/dashboards/dictionary/dashboard-translation-dictionary.element.ts b/src/Umbraco.Web.UI.Client/src/packages/translation/dashboards/dictionary/dashboard-translation-dictionary.element.ts
index 4154869964..03bd8de11f 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/translation/dashboards/dictionary/dashboard-translation-dictionary.element.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/translation/dashboards/dictionary/dashboard-translation-dictionary.element.ts
@@ -87,7 +87,6 @@ export class UmbDashboardTranslationDictionaryElement extends UmbLitElement {
 			// TODO: Generate URL for editing the dictionary item
 			const tableItem: UmbTableItem = {
 				id: dictionary.name ?? '',
-				icon: 'umb:book-alt',
 				data: [
 					{
 						columnAlias: 'name',
diff --git a/src/Umbraco.Web.UI.Client/src/shared/repository/data-source/extend-data-source-paged-response-data.function.ts b/src/Umbraco.Web.UI.Client/src/shared/repository/data-source/extend-data-source-paged-response-data.function.ts
index 2bbe8730d6..b1686406d2 100644
--- a/src/Umbraco.Web.UI.Client/src/shared/repository/data-source/extend-data-source-paged-response-data.function.ts
+++ b/src/Umbraco.Web.UI.Client/src/shared/repository/data-source/extend-data-source-paged-response-data.function.ts
@@ -21,7 +21,7 @@ import { Diff } from '@umbraco-cms/backoffice/utils';
 export function extendDataSourcePagedResponseData<
 	ExtendedDataType extends IncomingDataType,
 	IncomingDataType extends object = object,
-	MissingPropsType extends object = Omit<Diff<IncomingDataType, ExtendedDataType>, '$type'>,
+	MissingPropsType extends object = Diff<IncomingDataType, ExtendedDataType>,
 	// Maybe this Omit<..., "$ype"> can be removed, but for now it kept showing up as a difference, though its not a difference on the two types.
 	ToType = IncomingDataType & ExtendedDataType
 >(
diff --git a/src/Umbraco.Web.UI.Client/src/shared/repository/data-source/extend-data-source-response-data.function.ts b/src/Umbraco.Web.UI.Client/src/shared/repository/data-source/extend-data-source-response-data.function.ts
index d962cfe699..b4481d0b2d 100644
--- a/src/Umbraco.Web.UI.Client/src/shared/repository/data-source/extend-data-source-response-data.function.ts
+++ b/src/Umbraco.Web.UI.Client/src/shared/repository/data-source/extend-data-source-response-data.function.ts
@@ -21,8 +21,7 @@ import { Diff } from '@umbraco-cms/backoffice/utils';
 export function extendDataSourceResponseData<
 	ExtendedDataType extends IncomingDataType,
 	IncomingDataType extends object = object,
-	MissingPropsType extends object = Omit<Diff<IncomingDataType, ExtendedDataType>, '$type'>,
-	// Maybe this Omit<..., "$ype"> can be removed, but for now it kept showing up as a difference, though its not a difference on the two types.
+	MissingPropsType extends object = Diff<IncomingDataType, ExtendedDataType>,
 	ToType = IncomingDataType & ExtendedDataType
 >(response: DataSourceResponse<IncomingDataType>, appendData: MissingPropsType): DataSourceResponse<ToType> {
 	if (response.data === undefined) return response as unknown as DataSourceResponse<ToType>;
diff --git a/src/Umbraco.Web.UI.Client/src/shared/repository/folder-repository.interface.ts b/src/Umbraco.Web.UI.Client/src/shared/repository/folder-repository.interface.ts
index 3d9559bb2b..a16d32ae3d 100644
--- a/src/Umbraco.Web.UI.Client/src/shared/repository/folder-repository.interface.ts
+++ b/src/Umbraco.Web.UI.Client/src/shared/repository/folder-repository.interface.ts
@@ -2,23 +2,23 @@ import type {
 	CreateFolderRequestModel,
 	FolderModelBaseModel,
 	FolderReponseModel,
-	ProblemDetailsModel,
+	ProblemDetails,
 	UpdateFolderReponseModel,
 } from '@umbraco-cms/backoffice/backend-api';
 
 export interface UmbFolderRepository {
 	createFolderScaffold(parentId: string | null): Promise<{
 		data?: FolderReponseModel;
-		error?: ProblemDetailsModel;
+		error?: ProblemDetails;
 	}>;
 	createFolder(folderRequest: CreateFolderRequestModel): Promise<{
 		data?: string;
-		error?: ProblemDetailsModel;
+		error?: ProblemDetails;
 	}>;
 
 	requestFolder(unique: string): Promise<{
 		data?: FolderReponseModel;
-		error?: ProblemDetailsModel;
+		error?: ProblemDetails;
 	}>;
 
 	updateFolder(
@@ -26,10 +26,10 @@ export interface UmbFolderRepository {
 		folder: FolderModelBaseModel
 	): Promise<{
 		data?: UpdateFolderReponseModel;
-		error?: ProblemDetailsModel;
+		error?: ProblemDetails;
 	}>;
 
 	deleteFolder(id: string): Promise<{
-		error?: ProblemDetailsModel;
+		error?: ProblemDetails;
 	}>;
 }
diff --git a/src/Umbraco.Web.UI.Client/src/shared/repository/item-repository.interface.ts b/src/Umbraco.Web.UI.Client/src/shared/repository/item-repository.interface.ts
index 68093be25c..c1e7a02cb1 100644
--- a/src/Umbraco.Web.UI.Client/src/shared/repository/item-repository.interface.ts
+++ b/src/Umbraco.Web.UI.Client/src/shared/repository/item-repository.interface.ts
@@ -1,10 +1,10 @@
 import type { Observable } from '@umbraco-cms/backoffice/external/rxjs';
-import { ItemResponseModelBaseModel, ProblemDetailsModel } from '@umbraco-cms/backoffice/backend-api';
+import { ItemResponseModelBaseModel, ProblemDetails } from '@umbraco-cms/backoffice/backend-api';
 
 export interface UmbItemRepository<ItemType extends ItemResponseModelBaseModel> {
 	requestItems: (uniques: string[]) => Promise<{
 		data?: Array<ItemType> | undefined;
-		error?: ProblemDetailsModel | undefined;
+		error?: ProblemDetails | undefined;
 		asObservable?: () => Observable<Array<ItemType>>;
 	}>;
 	items: (uniques: string[]) => Promise<Observable<Array<ItemType>>>;
diff --git a/src/Umbraco.Web.UI.Client/src/shared/repository/tree-repository.interface.ts b/src/Umbraco.Web.UI.Client/src/shared/repository/tree-repository.interface.ts
index b1924711bd..4fda292e92 100644
--- a/src/Umbraco.Web.UI.Client/src/shared/repository/tree-repository.interface.ts
+++ b/src/Umbraco.Web.UI.Client/src/shared/repository/tree-repository.interface.ts
@@ -1,6 +1,6 @@
 import type { Observable } from '@umbraco-cms/backoffice/external/rxjs';
 import type { UmbTreeRootEntityModel, UmbTreeRootModel } from '@umbraco-cms/backoffice/tree';
-import { ProblemDetailsModel, EntityTreeItemResponseModel } from '@umbraco-cms/backoffice/backend-api';
+import { ProblemDetails, EntityTreeItemResponseModel } from '@umbraco-cms/backoffice/backend-api';
 
 export interface UmbPagedData<T> {
 	total: number;
@@ -13,25 +13,25 @@ export interface UmbTreeRepository<
 > {
 	requestTreeRoot: () => Promise<{
 		data?: TreeRootType;
-		error?: ProblemDetailsModel;
+		error?: ProblemDetails;
 	}>;
 
 	requestRootTreeItems: () => Promise<{
 		data?: UmbPagedData<TreeItemType>;
-		error?: ProblemDetailsModel;
+		error?: ProblemDetails;
 		asObservable?: () => Observable<TreeItemType[]>;
 	}>;
 
 	requestTreeItemsOf: (parentUnique: string | null) => Promise<{
 		data?: UmbPagedData<TreeItemType>;
-		error?: ProblemDetailsModel;
+		error?: ProblemDetails;
 		asObservable?: () => Observable<TreeItemType[]>;
 	}>;
 
 	// TODO: remove this when all repositories are migrated to the new interface items interface
 	requestItemsLegacy?: (uniques: string[]) => Promise<{
 		data?: Array<TreeItemType>;
-		error?: ProblemDetailsModel;
+		error?: ProblemDetails;
 		asObservable?: () => Observable<any[]>;
 	}>;
 
diff --git a/src/Umbraco.Web.UI.Client/src/shared/resources/resource.controller.ts b/src/Umbraco.Web.UI.Client/src/shared/resources/resource.controller.ts
index 63440f558b..fe11c93631 100644
--- a/src/Umbraco.Web.UI.Client/src/shared/resources/resource.controller.ts
+++ b/src/Umbraco.Web.UI.Client/src/shared/resources/resource.controller.ts
@@ -65,7 +65,7 @@ export class UmbResourceController extends UmbBaseController {
 				// Cancelled - do nothing
 				return {};
 			} else {
-				// ApiError - body could hold a ProblemDetailsModel from the server
+				// ApiError - body could hold a ProblemDetails from the server
 				if (typeof error.body !== 'undefined' && !!error.body) {
 					try {
 						(error as any).body = typeof error.body === 'string' ? JSON.parse(error.body) : error.body;
diff --git a/src/Umbraco.Web.UI.Client/storybook/stories/extending/tree.mdx b/src/Umbraco.Web.UI.Client/storybook/stories/extending/tree.mdx
index 43b7eedbd2..af8c97fc9e 100644
--- a/src/Umbraco.Web.UI.Client/storybook/stories/extending/tree.mdx
+++ b/src/Umbraco.Web.UI.Client/storybook/stories/extending/tree.mdx
@@ -111,7 +111,7 @@ export interface UmbTreeItemContext<T> {
 
 	requestChildren(): Promise<{
 		data: PagedResponse<T> | undefined;
-		error: ProblemDetailsModel | undefined;
+		error: ProblemDetails | undefined;
 		asObservable?: () => Observable<T[]>;
 	}>;
 	toggleContextMenu(): void;