The Drafts that I create on MailSpring client for my Gmail account doesn’t show up on the Gmail side and gets lost when I rebuild cache. This is unacceptable!
Steps to reproduce the behavior:
I can confirm the first part of your bug report: drafts created in Mailspring don’t get saved to the specified remote drafts folder. This is not actually a GMail issue - I don’t see drafts saved remotely on standard IMAP clients either.
However, I wonder why you’re rebuilding the cache often enough for it to be a problem. I’ve never done it in the 6 months I’ve been using Mailspring. And given that I’d expect “rebuilding the cache” to reset the local mail store to match what’s on the server, I don’t think what you report here is a bug. It’s just a consequence of the first bug, with drafts not being saved remotely.
The failure to sync drafts remotely is a major bug, though, IMO.
I decided to give MailSpring a try, and am loving it other than drafts not syncing to my Gmail account (haven’t tried with other accounts yet). If this issue isn’t fixable, I will have to keep searching for a Windows email client with a modern design that doesn’t force me to sync my Gmail to their servers.