diff --git a/.github/CODEOWNERS b/.github/CODEOWNERS
index a5c99b9c4..5b7508ff5 100644
--- a/.github/CODEOWNERS
+++ b/.github/CODEOWNERS
@@ -1,5 +1,2 @@
 # schema.json for manifest
 packages/vscode-ui5-language-assistant/resources/ @sapirpol
-
-# register manifest.json schema in workspace configuration - theia workaround
-packages/vscode-ui5-language-assistant/src/registerManifestSchema.ts @sapirpol @bd82
diff --git a/packages/vscode-ui5-language-assistant/src/extension.ts b/packages/vscode-ui5-language-assistant/src/extension.ts
index 59b50e5d7..b591e7c64 100644
--- a/packages/vscode-ui5-language-assistant/src/extension.ts
+++ b/packages/vscode-ui5-language-assistant/src/extension.ts
@@ -10,7 +10,6 @@ import {
   SERVER_PATH,
   ServerInitializationOptions,
 } from "@ui5-language-assistant/language-server";
-import { registerManifestSchema } from "./registerManifestSchema";
 
 let client: LanguageClient;
 
@@ -51,13 +50,6 @@ export async function activate(context: ExtensionContext): Promise<void> {
     clientOptions
   );
 
-  // This is a workaround to config `manifest.json` schema.
-  // Theia has a bug which there is no support for `contributes.jsonValidation`
-  //  - https://code.visualstudio.com/api/references/contribution-points#contributes.jsonValidation
-  if (process.env["THEIA_PARENT_PID"] !== undefined) {
-    registerManifestSchema();
-  }
-
   client.start();
 }
 
diff --git a/packages/vscode-ui5-language-assistant/src/manifestSchemaConfig.ts b/packages/vscode-ui5-language-assistant/src/manifestSchemaConfig.ts
deleted file mode 100644
index 4d4fbe68f..000000000
--- a/packages/vscode-ui5-language-assistant/src/manifestSchemaConfig.ts
+++ /dev/null
@@ -1,20 +0,0 @@
-export interface IJSONValidationExtensionPoint {
-  fileMatch: string[];
-  comment?: string;
-  url: string;
-}
-
-export const MANIFEST_FILE_MATCH = "manifest.json";
-export const MANIFEST_COMMENT =
-  "Automatic configuration for manifest.json schema - added by UI5 Language Assistant";
-
-export function getManifestSchemaConfigEntry(): IJSONValidationExtensionPoint {
-  const manifestSchemaConfig = {
-    fileMatch: [MANIFEST_FILE_MATCH],
-    comment: MANIFEST_COMMENT,
-    url:
-      "https://cdn.jsdelivr.net/gh/SAP/ui5-language-assistant/packages/vscode-ui5-language-assistant/resources/manifest-schema/rel-1.19/schema/schema.json",
-  };
-
-  return manifestSchemaConfig;
-}
diff --git a/packages/vscode-ui5-language-assistant/src/registerManifestSchema.ts b/packages/vscode-ui5-language-assistant/src/registerManifestSchema.ts
deleted file mode 100644
index c9d68fd6b..000000000
--- a/packages/vscode-ui5-language-assistant/src/registerManifestSchema.ts
+++ /dev/null
@@ -1,98 +0,0 @@
-/* istanbul ignore file - temporary workaround */
-import { isArray, find, some, clone, findIndex } from "lodash";
-import { workspace } from "vscode";
-import {
-  getManifestSchemaConfigEntry,
-  IJSONValidationExtensionPoint,
-  MANIFEST_COMMENT,
-  MANIFEST_FILE_MATCH,
-} from "./manifestSchemaConfig";
-
-/**
- *  The configuration will be written in workspace.settings
- */
-export function registerManifestSchema(): void {
-  const jsonSchemaConfig:
-    | IJSONValidationExtensionPoint
-    | undefined = workspace.getConfiguration().get("json.schemas");
-  if (isArray(jsonSchemaConfig)) {
-    const previousConfigEntryIndex = getIndexOfPreviousConfigEntry(
-      jsonSchemaConfig
-    );
-    if (previousConfigEntryIndex !== -1) {
-      updatePreviousConfigEntry(jsonSchemaConfig, previousConfigEntryIndex);
-    } else if (isMissingConfig(jsonSchemaConfig)) {
-      createConfig(jsonSchemaConfig);
-    } else {
-      // No change is needed
-    }
-  }
-}
-
-function isMissingConfig(
-  jsonSchemaConfig: IJSONValidationExtensionPoint[]
-): boolean {
-  const isMissingConfigEntry =
-    find(
-      jsonSchemaConfig,
-      (jsonSchemaConfigEntry: IJSONValidationExtensionPoint) => {
-        return some(
-          jsonSchemaConfigEntry.fileMatch,
-          (fileMatchEntry) => fileMatchEntry === MANIFEST_FILE_MATCH
-        );
-      }
-    ) === undefined;
-
-  return isMissingConfigEntry;
-}
-
-function createConfig(jsonSchemaConfig: IJSONValidationExtensionPoint[]): void {
-  const configEntry = getManifestSchemaConfigEntry();
-  const updatedSchemaConfig = clone(jsonSchemaConfig);
-  updatedSchemaConfig.push(configEntry);
-
-  configureSchemaInWorkspaceSettings(updatedSchemaConfig);
-}
-
-function getIndexOfPreviousConfigEntry(
-  jsonSchemaConfig: IJSONValidationExtensionPoint[]
-): number {
-  const previousConfigEntryIndex = findIndex(
-    jsonSchemaConfig,
-    (jsonSchemaConfigEntry: IJSONValidationExtensionPoint) => {
-      if (jsonSchemaConfigEntry.fileMatch.length === 1) {
-        // we are looking for exact match to be sure we are only changing 'settings.json' we added
-        return some(
-          jsonSchemaConfigEntry.fileMatch,
-          (fileMatchEntry) =>
-            fileMatchEntry === MANIFEST_FILE_MATCH &&
-            jsonSchemaConfigEntry.comment === MANIFEST_COMMENT
-        );
-      }
-
-      return false;
-    }
-  );
-
-  return previousConfigEntryIndex;
-}
-
-function updatePreviousConfigEntry(
-  jsonSchemaConfig: IJSONValidationExtensionPoint[],
-  previusConfigEntryIndex: number
-): void {
-  const updatedSchemaConfig = clone(jsonSchemaConfig);
-  updatedSchemaConfig[previusConfigEntryIndex] = getManifestSchemaConfigEntry();
-
-  configureSchemaInWorkspaceSettings(updatedSchemaConfig);
-}
-
-function configureSchemaInWorkspaceSettings(
-  updatedSchemaConfig: IJSONValidationExtensionPoint[]
-): void {
-  // We pass 'true' for global settings
-  //  - https://code.visualstudio.com/api/references/vscode-api#WorkspaceConfiguration
-  workspace
-    .getConfiguration()
-    .update("json.schemas", updatedSchemaConfig, true);
-}
diff --git a/packages/vscode-ui5-language-assistant/test/unit/registerManifestSchema-spec.ts b/packages/vscode-ui5-language-assistant/test/unit/registerManifestSchema-spec.ts
deleted file mode 100644
index a4ac754ec..000000000
--- a/packages/vscode-ui5-language-assistant/test/unit/registerManifestSchema-spec.ts
+++ /dev/null
@@ -1,23 +0,0 @@
-import { expect } from "chai";
-import { getManifestSchemaConfigEntry } from "../../src/manifestSchemaConfig";
-
-/**
- * fileMatch / comment values used to **identify** workspace settings
- * that have been automatically added by this vscode extension.
- */
-describe("the manifest schema entry configuration", () => {
-  it("file match must never be changed", () => {
-    const manifestSchemaConfig = getManifestSchemaConfigEntry();
-    expect(manifestSchemaConfig.fileMatch).to.exist;
-    expect(manifestSchemaConfig.fileMatch).to.have.length(1);
-    expect(manifestSchemaConfig.fileMatch[0]).to.equal("manifest.json");
-  });
-
-  it("comment must never be changed", () => {
-    const expectedComment =
-      "Automatic configuration for manifest.json schema - added by UI5 Language Assistant";
-    const manifestSchemaConfig = getManifestSchemaConfigEntry();
-    expect(manifestSchemaConfig.comment).to.exist;
-    expect(manifestSchemaConfig.comment).to.equal(expectedComment);
-  });
-});