HTTP/2 issues, HTTP/1.1 freezing

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

HTTP/2 fails the API, Ping, Chat, and Agent diagnostic checks in the network tab. Switching to HTTP/1.1 (as advised by Cursor staff in other bug reports) makes the Agent start working, but it still frequently gets stuck “thinking” indefinitely and never returns an answer.

Steps to Reproduce

Simply send a message to the agent.

Operating System

Windows 10/11

Current Cursor Version (Menu → About Cursor → Copy)

Version: 2.2.20 (system setup)
VSCode Version: 1.105.1
Commit: b3573281c4775bfc6bba466bf6563d3d498d1070
Date: 2025-12-12T06:29:26.017Z
Electron: 37.7.0
Chromium: 138.0.7204.251
Node.js: 22.20.0
V8: 13.8.258.32-electron.0
OS: Windows_NT x64 10.0.26100

For AI issues: add Request ID with privacy disabled

Request ID: 6d64a47c-de96-4798-b12e-0b238ae8eb9d
ConnectError: [internal] 301568:error:10000410:SSL routines:OPENSSL_internal:SSLV3_ALERT_HANDSHAKE_FAILURE:....\third_party\boringssl\src\ssl\tls_record.cc:486:SSL alert number 40

at _Gc.$streamAiConnect (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:12155:453319)
at async vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:585:89275
at async Object.run (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:12203:10221)
at async o (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:8603:1269)
at async Promise.allSettled (index 0)
at async Lzr.run (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:8603:6561)

Additional Information

To clarify, I don’t use a VPN or proxy, and I’m not on a corporate network. Switching to a different model doesn’t help. I haven’t encountered this issue before yesterday, nor at any point during the past month of use.

Does this stop you from using Cursor

Yes - Cursor is unusable

Shortly after writing this bug report, with the help of a friend, I was finally able to start using Cursor again. For anyone searching for a solution : just download an older version of the Cursor IDE. Here is the link: Download · Cursor. I personally downgraded to v2.0.77.