some tinkering with npm versions;

--- a/src/Tools/VSCode/extension/package.json	Wed Apr 07 18:13:02 2021 +0200
+++ b/src/Tools/VSCode/extension/package.json	Wed Apr 07 22:28:41 2021 +0200
@@ -17,7 +17,7 @@
         "url": "https://isabelle-dev.sketis.net"
     },
     "engines": {
-        "vscode": "^1.32.0"
+        "vscode": "^1.34.0"
     },
     "categories": [
         "Programming Languages"
@@ -549,7 +549,7 @@
         "vscode": "^1.1.36"
     },
     "dependencies": {
-        "vscode-languageclient": "~3.2.2",
-        "vscode-languageserver-types": "~3.14.0"
+        "vscode-languageclient": "~5.2.1",
+        "vscode-languageserver-types": "~3.16.0"
     }
 }