diff --git a/extensions/css-language-features/.vscode/launch.json b/extensions/css-language-features/.vscode/launch.json
index d6393141c5d..4f7166e6dce 100644
--- a/extensions/css-language-features/.vscode/launch.json
+++ b/extensions/css-language-features/.vscode/launch.json
@@ -23,8 +23,7 @@
 			"outFiles": [
 				"${workspaceFolder}/client/out/**/*.js"
 			],
-			"smartStep": true,
-			"preLaunchTask": "npm: compile"
+			"smartStep": true
 		},
 		{
 			"name": "Launch Tests",
@@ -39,8 +38,7 @@
 			"sourceMaps": true,
 			"outFiles": [
 				"${workspaceFolder}/client/out/test/**/*.js"
-			],
-			"preLaunchTask": "npm: compile"
+			]
 		},
 		{
 			"name": "Attach Language Server",
diff --git a/extensions/css-language-features/server/src/customData.ts b/extensions/css-language-features/server/src/customData.ts
index 3b253648d42..b5cbdc27c7a 100644
--- a/extensions/css-language-features/server/src/customData.ts
+++ b/extensions/css-language-features/server/src/customData.ts
@@ -3,7 +3,7 @@
  *  Licensed under the MIT License. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
 
-import { CSSData, ICSSDataProvider } from 'vscode-css-languageservice';
+import { CSSDataV1, ICSSDataProvider } from 'vscode-css-languageservice';
 import * as fs from 'fs';
 
 export function getDataProviders(dataPaths: string[]): ICSSDataProvider[] {
@@ -29,16 +29,19 @@ export function getDataProviders(dataPaths: string[]): ICSSDataProvider[] {
 	return providers;
 }
 
-function parseCSSData(source: string): CSSData {
+function parseCSSData(source: string): CSSDataV1 {
 	let rawData: any;
 
 	try {
 		rawData = JSON.parse(source);
 	} catch (err) {
-		return {};
+		return {
+			version: 1
+		};
 	}
 
 	return {
+		version: 1,
 		properties: rawData.properties || [],
 		atDirectives: rawData.atdirectives || [],
 		pseudoClasses: rawData.pseudoclasses || [],