Open PR says "GitHub CLI isn't installed" although gh is installed, on PATH and signed in (macOS desktop) #1283

Problem

Clicking Open PR pushes the branch, then shows:

GitHub CLI isn't installed
The branch was pushed, but creating the PR directly needs the GitHub CLI on this machine. Install it and sign in, then Open PR creates and updates PRs in one click.

But gh is installed, reachable from the default GUI PATH, and authenticated.

Environment

Environment

• ThinkRail: 0.3.2, desktop app, launched from the Dock
• macOS: <27.2>, Apple Silicon
• gh: 2.103.3 (2026-10-26), installed with Homebrew

What I checked

gh is linked into /usr/local/bin, which is on the default macOS GUI PATH:

$ ls -l /usr/local/bin/gh
lrwxr-xr-x  1 root  wheel  20 Nov  9 22:04 /usr/local/bin/gh -> /opt/homebrew/bin/gh

$ gh --version
gh version 2.103.3 (2026-10-26)

Auth is stored in the keychain, with repo scope:

$ gh auth status
github.com
  ✓ Logged in to github.com account oceaniver (keyring)
  - Active account: true
  - Git operations protocol: https
  - Token scopes: 'gist', 'read:org', 'repo', 'workflow'

I fully quit ThinkRail (⌘Q) and relaunched it after creating the symlink.

Expected

Open PR finds gh and creates the pull request.

Actual

The "GitHub CLI isn't installed" notice is shown every time, so the PR has to be opened in the browser.

Notes

This may be related to #686 (adopting the login-shell PATH for Dock/Finder launches). However, gh here is also reachable through /usr/local/bin, so a missing PATH entry alone shouldn't explain it. If gh fails or times out for another reason, it may be reported as "not installed" (see the follow-up note in #1136 about how gh probe failures are mapped).