Unable to post reply via email

I am using Email mode and in each email there is a link to visit the topic, but it also says I can use Reply to post a reply. I am using gmail via browser. I tried this but the email bounced with message below. The body was certainly longer than 20 characters:

We’re sorry, but your email message to [“nodered+b27f01b2bae9b0d34f744e016c43752e@discoursemail.com”] (titled Re: [Node-RED Forum] [Meta] Email mode and max email limit) didn’t work.

Reason:

Body is too short (minimum is 20 characters)

If you can correct the problem, please try again.

Ah, in fact it was less than 20 characters as it strips off quoted text. Sorry for the noise.