diff --git a/extensions/typescript-language-features/src/tsServer/spawner.ts b/extensions/typescript-language-features/src/tsServer/spawner.ts
index 891735c80c3..88c31e89a69 100644
--- a/extensions/typescript-language-features/src/tsServer/spawner.ts
+++ b/extensions/typescript-language-features/src/tsServer/spawner.ts
@@ -10,7 +10,7 @@ import { ClientCapabilities, ClientCapability, ServerType } from '../typescriptS
 import API from '../utils/api';
 import { SyntaxServerConfiguration, TsServerLogLevel, TypeScriptServiceConfiguration } from '../utils/configuration';
 import { Logger } from '../utils/logger';
-import { isWeb } from '../utils/platform';
+import { isWeb, isWebAndHasSharedArrayBuffers } from '../utils/platform';
 import { TypeScriptPluginPathsProvider } from '../utils/pluginPathsProvider';
 import { PluginManager } from '../utils/plugins';
 import { TelemetryReporter } from '../utils/telemetry';
@@ -261,6 +261,10 @@ export class TypeScriptServerSpawner {
 
 		args.push('--validateDefaultNpmLocation');
 
+		if (isWebAndHasSharedArrayBuffers()) {
+			args.push('--enableProjectWideIntelliSenseOnWeb');
+		}
+
 		return { args, tsServerLogFile, tsServerTraceDirectory };
 	}
 
diff --git a/extensions/typescript-language-features/web/webServer.ts b/extensions/typescript-language-features/web/webServer.ts
index 17b9b27d880..58ae976ee50 100644
--- a/extensions/typescript-language-features/web/webServer.ts
+++ b/extensions/typescript-language-features/web/webServer.ts
@@ -544,7 +544,7 @@ async function initializeSession(args: string[], extensionUri: URI, platform: st
 	};
 
 	let sys: ServerHostWithImport;
-	if (serverMode === ts.LanguageServiceMode.Semantic) {
+	if (hasArgument(args, '--enableProjectWideIntelliSenseOnWeb')) {
 		const connection = new ClientConnection<Requests>(ports.sync);
 		await connection.serviceReady();