Do not use json with comments.

language-configuration.json

@@ -1,21 +1,21 @@
 {
     "comments": {
-        "lineComment": "@c",
+        "lineComment": "@c"
     },
     "brackets": [
         ["{", "}"],
         ["[", "]"],
-        ["(", ")"],
+        ["(", ")"]
     ],
     "autoClosingPairs": [
         ["{", "}"],
         ["[", "]"],
-        ["(", ")"],
+        ["(", ")"]
     ],
     "surroundingPairs": [
         ["{", "}"],
         ["[", "]"],
         ["(", ")"],
-        ["`", "'"],
-    ],
+        ["`", "'"]
+    ]
 }

tsconfig.json

@@ -4,17 +4,17 @@
         "target": "ES2019",
         "outDir": "out",
         "lib": [
-            "ES2019",
+            "ES2019"
         ],
         "esModuleInterop": true,
         "strictNullChecks": true,
         "sourceMap": true,
         "rootDir": "src",
         "strict": true,
-        "noImplicitReturns": true,
+        "noImplicitReturns": true
     },
     "exclude": [
         "node_modules",
-        "*.config.ts",
-    ],
+        "*.config.ts"
+    ]
 }