Regression: Remote-SSH Open Folder picker does not expand directories in Insiders 1.133

Does this issue occur when all extensions are disabled?: Yes

- VS Code Version: 1.133.0-insider (5a36a9c68ce6300f94225aff5f8db533671af98b)
- OS Version: Windows 11 local → Ubuntu 24.04.4 LTS remote

Steps to Reproduce:
1. Install VS Code Insiders 1.133 on Windows
2. Connect to a remote Ubuntu 24.04 host via Remote-SSH
3. Open a folder on the remote host
3. Select File → Open Folder to open the remote folder picker
4. Click the disclosure chevron (▶) beside a directory such as /var, /home, /usr, or /etc

Expected: Folder expands to show its contents
Actual: Nothing happens. The chevron does not respond to clicks. No error notification, no visual feedback.

Controlled A/B Testing
VS Code Stable 1.127.0 works correctly against the same remote hosts with the identical local machine, GPU, SSH configuration, and user account. Only Insiders is affected.

VS Code Stable 1.127 → same remote hosts | ✅ Chevrons expand normally
VS Code Insiders 1.133 → Remote Host A (Ubuntu 24.04) | ❌ Chevrons do not respond
VS Code Insiders 1.133 → Remote Host B (Ubuntu 24.04) | ❌ Reproduces on second independent host
Fresh Windows Insiders install (no prior state) | ❌ Still broken
All Insiders local state deleted (%APPDATA%\Code - Insiders) | ❌ Still broken
Insiders shared state deleted (.vscode-insiders-shared) | ❌ Still broken
Settings Sync disabled | ❌ Still broken
Remote Insiders server deleted (~/.vscode-server-insiders) and freshly redeployed | ❌ Still broken
Fresh SSH authority / new connection | ❌ Still broken
Direct remote filesystem access (terminal, SFTP) | ✅ Filesystem is healthy
Same Windows machine, same GPU, same SSH config → Stable | ✅ Works perfectly

Relevant Log Entry
The Insiders Extension Host log contains the following error that does not appear in Stable:

command 'remote-internal.setActiveFolders' not found
This error correlates with the broken environment but has not been confirmed as the direct cause of the chevron failure. It may indicate a broader command-registration issue in the Insiders remote-explorer or remote-SSH extension host initialization. Including it as a diagnostic lead.

What Has Been Ruled Out
GPU / rendering: Stable renders identical chevrons correctly on the same GPU. The chevron is visually present; it simply doesn't respond to interaction.
Local state corruption: Full uninstall + clean reinstall of Insiders with no migrated state reproduces the bug.
Remote server corruption: Deleting ~/.vscode-server-insiders and redeploying reproduces the bug.
Network / SSH issues: Stable connects and operates normally over the same SSH connection. Terminal and file operations work fine in Insiders — only the explorer tree interaction is broken.
Single-host fluke: Reproduced independently on two separate Ubuntu 24.04 servers.
Settings Sync interference: Disabled; still reproduces.
Extensions: Reproduces with all extensions disabled.

Start by reproducing the folder-picker failure with Insiders 1.133 over Remote-SSH and inspect the Insiders Extension Host log, especially the missing `remote-internal.setActiveFolders` command. Compare the same actions with Stable 1.127 and verify that directory chevrons expand on both tested Ubuntu hosts without command errors.

Written by the indexing model from the issue text.