Moments after an email sends, it'll come back as draft

Problem

I’ll send an email. Mailspring shows it as sent after the brief [configured] wait period. I’ll come back later and find that it came back as draft, and the Gmail web app (the source of truth) confirms that no email was sent. When I’m watching it, it seems to come back as soon as a minute later.

Context

Happens frequently but not always. It happens about 50% of the time. It’s not clear what the common factor is. On this system, I tend to write a lot of replies but very few new emails. They tend to be simple text (no images, no attachments).

Seems related, but no one ever responded:

Email Provider

Gmail

Setup

  • OS and Version: EndeavorOS (Arch). Rolling updates.
  • Installation Method: AUR
  • Mailspring Version: 1.10.3-1 (just upgraded to 1.10.5-1 as I’m writing this; we’ll see if it helps)