Problems (red) on Java files/packages mostly after cleaning workspace

I have a problem where Java files and packages in vscode stay red showing a problem. This happens mostly after cleaning workspace.
I use workspaces with many different maven projects in each and it occures in all of them.

The problems shown in the problems view are The import foo.bar cannot be resolved and MyJavaClass cannot be resolved to a type. I can only fix this, if I open every single file once. Then the problmes go away automatically, but this is really annoying to do.

Environment

• Operating System: Windows 10 20H2
• JDK version:
• Visual Studio Code version: 1.69.2
• Java extension version: 1.9.0

Steps To Reproduce

Clean workspace with multiple folders of multimodule maven projects. At least using my projects this happens.

Current Result

VS Code showing a bunch of problems and red projects

Expected Result

No problems in VS Code and no red projects.

Additional Informations

No more hints i can give.

使用包含多个文件夹和多模块 Maven 项目的干净 VS Code 工作区，在所述的 Windows 10、VS Code 1.69.2 和 Java extension 1.9.0 环境中复现该报告。确认 import 和类型是否在每个文件都被打开之前仍保持未解析；无需打开每个文件，只有 Problems view 和项目标记清除后才算完成。