ERR_NGROK_3905: The content-length header could not be successfully updated for action type ACTIONTYPE - ngrok documentation

What does ERR_NGROK_3905 mean?

ngrok returns ERR_NGROK_3905 with this message:

The content-length header could not be successfully updated for action type <ACTIONTYPE>

Troubleshoot ERR_NGROK_3905 with your AI agent. Connect it to the ngrok MCP server, then ask what caused the error and how to fix it.

Where can I get more help with ERR_NGROK_3905?

Email support@ngrok.com and include the error code.