Restore operations happen in foreground in Class Library projects in Visual Studio

[OronDF343]

Describe the bug

In Class Library projects in Visual Studio, package restores are performed in the foreground, which causes Visual Studio to become unresponsive.

For example, changing the destination will cause Visual Studio to become unresponsive while files are deleted from their old location one by one. In addition, the file deletions are performed via the system shell, which may pop up the progress dialog from File Explorer, and that also causes mouse/keyboard focus to be lost temporarily, so I cannot continue work in another window during this operation.

To Reproduce

Steps to reproduce the behavior:

1. Create a new Class Library project (SDK-style) in Visual Studio. Not sure if the target framework matters, mine has multi-targeting: net6.0;netstandard2.1;net472
2. Add a new file named libman.json with the following content and save it:

{
  "version": "1.0",
  "defaultProvider": "cdnjs",
  "libraries": [
    {
      "library": "tom-select@2.2.2",
      "destination": "lib/tom-select"
    }
  ]
}

3. Change the destination to lib/tom-select2 and save the file again. Visual Studio will now become unresponsive.

Expected behavior

The restore operation should happen in the background, just like projects targeting Microsoft.NET.Sdk.Web.

Screenshots

This demonstrates what I mean by "deleting one by one using the system shell":

Additional context

• Visual Studio version 17.6.0
• Microsoft Library Manager version 2.1.178.29796
• Windows 10 version 22H2