# OAuth MCP login via custom protocol fails on Linux AppImage

**URL:** <https://forum.cursor.com/t/oauth-mcp-login-via-custom-protocol-fails-on-linux-appimage/124413>\
**Category:** Bug Reports\
**Created:** [July 31, 2025, 3:03am UTC](https://forum.cursor.com/t/oauth-mcp-login-via-custom-protocol-fails-on-linux-appimage/124413 "2025-07-31T03:03:26Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![fergaete](https://sea3.discourse-cdn.com/cursor1/user_avatar/forum.cursor.com/fergaete/32/73978_2.png) [@fergaete](https://forum.cursor.com/u/fergaete)\
**Post date:** [July 31, 2025, 3:03am UTC](https://forum.cursor.com/t/oauth-mcp-login-via-custom-protocol-fails-on-linux-appimage/124413/1 "2025-07-31T03:03:26Z")

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### Describe the Bug

When using an MCP with OAuth (e.g., Notion) on Linux via AppImage, the cursor:// protocol handler doesn’t successfully authorize the MCP server after completing the OAuth flow.

After the browser completes the flow and attempts to redirect to cursor://…, Cursor opens a blank tab showing the callback URL as plaintext and does not complete the login.

### Steps to Reproduce

1. Download Cursor AppImage and run it on Linux
2. Register a desktop entry with:

- MimeType=x-scheme-handler/cursor;

1. Register an MCP server with OAuth (e.g., Notion)
2. Cursor displays Needs login
3. Click login, complete OAuth flow in the browser
4. Browser tries to open cursor://anysphere.cursor-retrieval/oauth/user/Notion/callback?code=…
5. Cursor opens a new tab, but does not process or finalize the OAuth login

### Expected Behavior

The app should process the cursor://… URL, extract the code, and finish OAuth handshake with the MCP server.

### Operating System

Linux

### Current Cursor Version (Menu → About Cursor → Copy)

Version: 1.3.6  
VSCode Version: 1.99.3  
Commit: 68b8fe7396ea37d8acdaaaa08ba316ba359a4160  
Date: 2025-07-30T18:07:31.095Z  
Electron: 34.5.1  
Chromium: 132.0.6834.210  
Node.js: 20.19.0  
V8: 13.2.152.41-electron.0  
OS: Linux x64 6.11.0-29-generic

### Does this stop you from using Cursor

Yes - Cursor is unusable

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<div class="post-metadata">

**Author:** ![sanjeed5](https://sea3.discourse-cdn.com/cursor1/user_avatar/forum.cursor.com/sanjeed5/32/9610_2.png) [@sanjeed5](https://forum.cursor.com/u/sanjeed5)\
**Post date:** [August 18, 2025, 2:45pm UTC](https://forum.cursor.com/t/oauth-mcp-login-via-custom-protocol-fails-on-linux-appimage/124413/2 "2025-08-18T14:45:29Z")

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Thanks for reporting this!

Can you please update to the latest Cursor version and check if it works?

Please let us know if this still happens after updating.

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**Author:** ![system](https://sea3.discourse-cdn.com/cursor1/user_avatar/forum.cursor.com/system/32/99069_2.png) [@system](https://forum.cursor.com/u/system)\
**Post date:** [September 9, 2025, 2:45pm UTC](https://forum.cursor.com/t/oauth-mcp-login-via-custom-protocol-fails-on-linux-appimage/124413/3 "2025-09-09T14:45:33Z")

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