REST Client extension: response panel not shown unless editor is split first (regression after Cursor upgrade)

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

After upgrading Cursor, the REST Client extension (Huachao Mao — no extension update) sends HTTP requests successfully (status bar shows timing), but the response panel/tab never appears unless I manually split the editor first (Ctrl+).

The extension itself has not changed; this appears to be a Cursor editor API / layout regression introduced by the Cursor upgrade.

Steps to Reproduce

  1. Install REST Client extension (v0.25.0)
  2. Open a .http file with a request
  3. Click Send Request
  4. Observe: status bar shows request completed, but no response tab opens
  5. Split editor with Ctrl+, send request again → response appears in the split panel

Expected Behavior

Response tab opens automatically beside the request editor, same as earler version of Cursor.

Operating System

Windows 10/11

Version Information

Version: 3.7.42
VSCode Version: 1.105.1
Commit: 5702c9cfca656d8710fad58402fe37f14345e3a0
Date: 2026-06-15T19:39:42.738Z
Build Type: Stable
Release Track: Default
OS: Windows_NT x64 10.0.19045
Architecture: x64
Layout: Editor (Agent sidebar open, auxiliary bar width ~885px)
Theme: Cursor Dark Midnight

REST Client: 0.25.0 (humao.rest-client, publisher: Huachao Mao)
REST Client config: rest-client.previewColumn not customized (default: “beside”)

Additional Information

Root Cause (suspected)
REST Client resolves the preview column via window.activeTextEditor.viewColumn + 1 when rest-client.previewColumn is beside (default). On Cursor, viewColumn is often undefined (e.g. when the Agent/Chat panel is open), so preview column resolution fails silently — the HTTP request completes but no response tab is created.

Related upstream discussion (same symptom, same workaround): Expriencing Issue on Cursor · Issue #1434 · Huachao/vscode-restclient · GitHub

This is a Cursor compatibility issue, not an extension change.

Does this stop you from using Cursor

No - Cursor works, but with this issue

Hey @tcdnw!

This looks like an unmaintained VSCode Extension, and it’s unlikely we’ll expedite a change here just to support this extension!

Did you try the fork that was mentioned on the GitHub issue? GitHub - kit1211/cursor-rest-client-plus: REST API client for Cursor/VS Code with Faker variables, response history, IDE diff compare, and Cursor preview fixes · GitHub