Does this issue occur when all extensions are disabled?: N/A

• VS Code Version: 1.63.2
• OS Version: Windows 10 Enterprise, Version 20H2, OS Build 19042.1415

I raised an issue regarding this in OmniSharp-VSCode's repo, but they suggested that the issue should be raised here.

Steps to Reproduce:

For weeks, i've noticed that among the all extensions i've installed, the C# one is the only one has this issue. Go to the Extensions view. Click Install Another Version... on the menu for the C# extension. Observe that after hanging for a long time (it took me 56 seconds), the expected list of versions finally shows up.