[vscode-desktop]: Can't preview private ports

[filiptronicek]

Bug description

Private Gitpod ports can't be accesed by the VS Code Desktop WebViews, rendering them unusable (well, not rendering them at all 😝)

I think this is a similar issue to #4924 (comment), at least the root cause - we need to send a cookie / header with the request, because the WebView does not auth at all, so it receives a 401, which is expected.

Steps to reproduce

1. Open a workspace, which exposes a port right away so no further repro setup is required, for example the Node.js demo
2. Open the top context menu (hamburger), click Gitpod: Open in VS Code Insiders
3. On your desktop VS Code, start
4. Go to port on the bottom of the screen and click the book with the magnifying glass to preview in Simple Browser.
5. Observe a white blank screen

Workspace affected

all of 'em

Expected behavior

All ports, private and public can be accessed via the VS Code Desktop integration.

Example repository

https://github.com/gitpod-io/template-typescript-node

Anything else?

No response

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[mustard-mh]

It's correct since 3000 with frame is blocked by server (see error log), try with other port, and it works well

3000	8080

[mustard-mh]

You can disable that blocking behavior by comment this line and re-build + re-serve the server