ERR_NGROK_4408: Feature request suggestions must be between 1 and MAXLEN characters, got LENGTH - ngrok documentation

What does ERR_NGROK_4408 mean?

ngrok returns ERR_NGROK_4408 with this message:

Feature request suggestions must be between 1 and <MAXLEN> characters, got <LENGTH>.

Where can I get more help with ERR_NGROK_4408?

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