Autocomplete doesn't populate dropdown

Autocomplete is completely useless for me. It works sometimes, after at least a minute of loading. Most of the time it never loads.
After enabling server trace I noticed that the language server does return options, but it doesn't load in the intellisense popup, which is stuck on 'Loading...'.
Same goes for 'Go to Definition' language server returns the file, but VSCode is stuck loading (blue loading indicator at top of window) and doesn't open the file.

Environment

• Operating System: Windows
• JDK version: 1.8.0_201-b09
• Visual Studio Code version: 1.33.0
• Java extension version: 0.42.1

This happens on small (10 files) and larger projects.

まず、記載された Java、JDK、拡張機能、Windows のバージョンで Visual Studio Code におけるオートコンプリートと Go to Definition の失敗を再現し、その後、サーバートレースと読み込みの挙動を調査します。完了の条件は、返された補完候補が IntelliSense ポップアップに表示され、返された定義ファイルが読み込み中のままにならずに開くことです。