The problem
Description
After completing the OAuth authorization flow in the browser, GitHub Desktop fails to receive the auth token and shows "An unknown error occurred." The app is stuck in an unauthenticated state and the issue persists across multiple sign-in attempts.
Steps to reproduce
Open GitHub Desktop on macOS Tahoe 26.5
Go to GitHub Desktop > Settings > Accounts
Click "Sign in to GitHub.com" — the browser opens the GitHub authorization page
GitHub correctly identifies the account and presents the "Authorize GitHub Desktop" screen
Click "Continue" — GitHub authorizes the app successfully on the web side
GitHub Desktop receives the callback and immediately shows: "An unknown error occurred."
The app remains signed out; attempting to fetch/push shows an "Authentication failed" error
Expected behavior
After clicking "Continue" in the browser, the OAuth token should be passed back to GitHub Desktop and the user should be signed in successfully.
Actual behavior
The app shows "An unknown error occurred." and the user remains unauthenticated. The OAuth token registered on GitHub's side shows as "Never used", confirming the token is never successfully received by the app.
Environment
macOS version: Tahoe 26.5
GitHub Desktop version: 3.5.11
Browser used for OAuth: Chrome
Additional context
The GitHub side of the authorization completes without issue — the OAuth app entry for GitHub Desktop appears in GitHub Settings > Authorized OAuth Apps after each attempt. The failure appears to occur during the x-github-client:// URL scheme callback from the browser back to the app, which may be affected by changes to how macOS Tahoe handles custom URL scheme redirects or app entitlements.
Release version
3.5.11
Operating system
Mac OS Tahoe 26.5
Steps to reproduce the behavior
Steps to reproduce
Open GitHub Desktop on macOS Tahoe 26.5
Go to GitHub Desktop > Settings > Accounts
Click "Sign in to GitHub.com" — the browser opens the GitHub authorization page
GitHub correctly identifies the account and presents the "Authorize GitHub Desktop" screen
Click "Continue" — GitHub authorizes the app successfully on the web side
GitHub Desktop receives the callback and immediately shows: "An unknown error occurred."
The app remains signed out; attempting to fetch/push shows an "Authentication failed" error
Log files
No response
Screenshots
Additional context
Additional context
The GitHub side of the authorization completes without issue — the OAuth app entry for GitHub Desktop appears in GitHub Settings > Authorized OAuth Apps after each attempt. The failure appears to occur during the x-github-client:// URL scheme callback from the browser back to the app, which may be affected by changes to how macOS Tahoe handles custom URL scheme redirects or app entitlements.
The problem
Description
After completing the OAuth authorization flow in the browser, GitHub Desktop fails to receive the auth token and shows "An unknown error occurred." The app is stuck in an unauthenticated state and the issue persists across multiple sign-in attempts.
Steps to reproduce
Open GitHub Desktop on macOS Tahoe 26.5
Go to GitHub Desktop > Settings > Accounts
Click "Sign in to GitHub.com" — the browser opens the GitHub authorization page
GitHub correctly identifies the account and presents the "Authorize GitHub Desktop" screen
Click "Continue" — GitHub authorizes the app successfully on the web side
GitHub Desktop receives the callback and immediately shows: "An unknown error occurred."
The app remains signed out; attempting to fetch/push shows an "Authentication failed" error
Expected behavior
After clicking "Continue" in the browser, the OAuth token should be passed back to GitHub Desktop and the user should be signed in successfully.
Actual behavior
The app shows "An unknown error occurred." and the user remains unauthenticated. The OAuth token registered on GitHub's side shows as "Never used", confirming the token is never successfully received by the app.
Environment
macOS version: Tahoe 26.5
GitHub Desktop version: 3.5.11
Browser used for OAuth: Chrome
Additional context
The GitHub side of the authorization completes without issue — the OAuth app entry for GitHub Desktop appears in GitHub Settings > Authorized OAuth Apps after each attempt. The failure appears to occur during the x-github-client:// URL scheme callback from the browser back to the app, which may be affected by changes to how macOS Tahoe handles custom URL scheme redirects or app entitlements.
Release version
3.5.11
Operating system
Mac OS Tahoe 26.5
Steps to reproduce the behavior
Steps to reproduce
Open GitHub Desktop on macOS Tahoe 26.5
Go to GitHub Desktop > Settings > Accounts
Click "Sign in to GitHub.com" — the browser opens the GitHub authorization page
GitHub correctly identifies the account and presents the "Authorize GitHub Desktop" screen
Click "Continue" — GitHub authorizes the app successfully on the web side
GitHub Desktop receives the callback and immediately shows: "An unknown error occurred."
The app remains signed out; attempting to fetch/push shows an "Authentication failed" error
Log files
No response
Screenshots
Additional context
Additional context
The GitHub side of the authorization completes without issue — the OAuth app entry for GitHub Desktop appears in GitHub Settings > Authorized OAuth Apps after each attempt. The failure appears to occur during the x-github-client:// URL scheme callback from the browser back to the app, which may be affected by changes to how macOS Tahoe handles custom URL scheme redirects or app entitlements.