diff --git a/package-lock.json b/package-lock.json
index e4980605..f29605ac 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -79,9 +79,9 @@
             "dev": true
         },
         "@types/vscode": {
-            "version": "1.42.0",
-            "resolved": "https://registry.npmjs.org/@types/vscode/-/vscode-1.42.0.tgz",
-            "integrity": "sha512-ds6TceMsh77Fs0Mq0Vap6Y72JbGWB8Bay4DrnJlf5d9ui2RSe1wis13oQm+XhguOeH1HUfLGzaDAoupTUtgabw==",
+            "version": "1.50.0",
+            "resolved": "https://registry.npmjs.org/@types/vscode/-/vscode-1.50.0.tgz",
+            "integrity": "sha512-QnIeyi4L2DiD9M2bAQKRzT/EQvc80qP9UL6JD5TiLlNRL1khIDg4ej4mDSRbtFrDAsRntFI1RhMvdomUThMsqg==",
             "dev": true
         },
         "abab": {
diff --git a/package.json b/package.json
index 22e91b40..ea24e2dd 100644
--- a/package.json
+++ b/package.json
@@ -8,7 +8,7 @@
     "license": "MIT",
     "icon": "resources/LeetCode.png",
     "engines": {
-        "vscode": "^1.42.0"
+        "vscode": "^1.50.0"
     },
     "repository": {
         "type": "git",
@@ -243,6 +243,11 @@
                 }
             ],
             "editor/context": [
+                {
+                    "submenu": "leetcode.editorAction"
+                }
+            ],
+            "leetcode.editorAction": [
                 {
                     "command": "leetcode.testSolution",
                     "group": "leetcode@1"
@@ -261,6 +266,12 @@
                 }
             ]
         },
+        "submenus": [
+            {
+                "id": "leetcode.editorAction",
+                "label": "LeetCode"
+            }
+        ],
         "configuration": [
             {
                 "title": "LeetCode",
@@ -678,7 +689,7 @@
         "@types/mocha": "^2.2.42",
         "@types/node": "^14.14.33",
         "@types/require-from-string": "^1.2.0",
-        "@types/vscode": "1.42.0",
+        "@types/vscode": "1.50.0",
         "tslint": "^5.20.1",
         "typescript": "^4.3.2"
     },
diff --git a/src/explorer/LeetCodeTreeDataProvider.ts b/src/explorer/LeetCodeTreeDataProvider.ts
index 69445bbb..2bfbe497 100644
--- a/src/explorer/LeetCodeTreeDataProvider.ts
+++ b/src/explorer/LeetCodeTreeDataProvider.ts
@@ -23,7 +23,7 @@ export class LeetCodeTreeDataProvider implements vscode.TreeDataProvider<LeetCod
 
     public async refresh(): Promise<void> {
         await explorerNodeManager.refreshCache();
-        this.onDidChangeTreeDataEvent.fire();
+        this.onDidChangeTreeDataEvent.fire(null);
     }
 
     public getTreeItem(element: LeetCodeNode): vscode.TreeItem | Thenable<vscode.TreeItem> {
diff --git a/src/utils/workspaceUtils.ts b/src/utils/workspaceUtils.ts
index c129f8db..81072be7 100644
--- a/src/utils/workspaceUtils.ts
+++ b/src/utils/workspaceUtils.ts
@@ -18,9 +18,8 @@ export async function selectWorkspaceFolder(): Promise<string> {
             return workspaceFolderSetting;
         }
     }
-    const workspaceFolders: vscode.WorkspaceFolder[] = vscode.workspace.workspaceFolders || [];
     let needAsk: boolean = true;
-    for (const folder of workspaceFolders) {
+    for (const folder of vscode.workspace.workspaceFolders || []) {
         if (isSubFolder(folder.uri.fsPath, workspaceFolderSetting)) {
             needAsk = false;
         }
@@ -47,7 +46,7 @@ export async function selectWorkspaceFolder(): Promise<string> {
                 await vscode.commands.executeCommand("vscode.openFolder", vscode.Uri.file(workspaceFolderSetting), true);
                 return "";
             case OpenOption.addToWorkspace:
-                vscode.workspace.updateWorkspaceFolders(workspaceFolders.length, 0, { uri: vscode.Uri.file(workspaceFolderSetting) });
+                vscode.workspace.updateWorkspaceFolders(vscode.workspace.workspaceFolders?.length ?? 0, 0, { uri: vscode.Uri.file(workspaceFolderSetting) });
                 break;
             default:
                 return "";