Misleading error message about proposal APIs when attempting to use a feature of an extension

[glektarssza]

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

Version: 1.63.0-insider (system setup)
Commit: d450b04c783dfa6f83dc439017767acccd4e9fac
Date: 2021-11-17T05:21:29.351Z
Electron: 13.5.2
Chromium: 91.0.4472.164
Node.js: 14.16.0
V8: 9.1.269.39-electron.0
OS: Windows_NT x64 10.0.22000

Steps to Reproduce:

1. Install ms-dotnettools.csharp
2. Create a .NET project using dotnet new classlib
3. Attempt to select a project using the command Omnisharp: Select Project

Expected Results:

• Quick picker for selecting a project opens

Actual Results:

• An error notification appears with the following text, which is misleading/confusing as it says that the extension both does and does not use an proposal API:

Extension 'ms-dotnettools.csharp' CANNOT use API proposal: quickPickSeparators.
According to its package.json#enabledApiProposals-property it wants: <none>.
 You MUST start in extension development mode or use the following command line switch: --enable-proposed-api ms-dotnettools.csharp

Other Notes:

• Was working before the this morning's Insider's update
• Issue manifests in the following repository: https://github.com/glektarssza/sdl2-dotnet

[gjsjohnmurray]

See #136964 for details of migrating extensions which use proposed API.

[jrieken]

which is misleading/confusing as it says that the extension both does and does not use an proposal API:

I see how it is misleading but the gist is that the extension doesn't name the proposal in its package.json#enabledApiProposals-property and therefore cannot use it