Offline mode - Ubuntu - Only read messages, can't write nor mark them

Description

I can use Mailspring normally when online and also offline, with no internet connection at all (wired and wireless off). When offline, the orange “One or more accounts are having connection issues” is shown, but I can read, write, mark and move the emails, on any of my 3 Gmail accounts.

But recently, my company has started to block the IMAP protocol and Mailspring shows a red warning with the message “Several of your accounts are having issues.”. At this point I can’t do anything but read the emails, but them didn’t are marked as read. I can’t mark, move nor write emails.

On any interaction, a warning says “In order to perform actions on this mailbox, you need to resolve the sync issue. Visit Preferences > Accounts for more information.”, and nothing can be done.

When the PC/laptop is connected to a network with the IMAP protocol unblocked, it works again.

When the PC/laptop is disconnected from the network with the IMAP protocol blocked, the orange warning message appears but the wrong behavior continues, with the “In order to perform actions on this mailbox, you need to resolve the sync issue. Visit Preferences > Accounts for more information.” warning on every action. To make it works again, Mailspring has to be closed and reopened.

To Reproduce…

With a working Mailspring installation, block the access to IMAP protocol.

Steps to reproduce the behavior:

  1. Connect the PC/laptop to a network that blocks the IMAP protocol.
  2. Wait for the red warning box.
  3. Read a message.
  4. Mark the message with an star.
  5. The message is not starred.
  6. Write a new email.
  7. The warning says “In order to perform actions on this mailbox, you need to resolve the sync issue. Visit Preferences > Accounts for more information.”.
  8. The email can’t be written.

Expected Behavior

Although the IMAP protocol is blocked, the expected behavior is to work offline, like with the orange warning box.

Screenshots

Setup

  • OS and Version: Ubuntu Linux 21.04
  • Installation Method: snapcraft (Ubuntu software)
  • Mailspring Version: 1.9.1

Additional Context

I’m filling this as a bug because it isn’t a sync issue. The 3 Gmail accounts are already synced and working.

Error Details

Mailspring Version: 1.9.1-30ef802f
Platform: linux
Account State: sync_error
Account Provider: gmail
IMAP Server: imap.gmail.com
SMTP Server: smtp.gmail.com
--------------------------------------------
473734 [2021-07-19 09:11:44.134] [background] [info] Fetching XOAuth2 access token (gmail) for ab1c444e
473734 [2021-07-19 09:11:44.291] [background] [info] Marking all folders as `busy`
473734 [2021-07-19 09:11:44.295] [background] [info] Syncing folder list...
473734 [2021-07-19 09:11:44.441] [background] [critical] 
***
*** Mailspring Sync 
*** An exception occurred during program execution: 
*** {"debuginfo":"syncFoldersAndLabels - fetchAllFolders","key":"ErrorCertificate","retryable":false,"what":"std::exception"}
***

Any update on this issue?

Regards…

This error is stil present on v1.9.2

Any update?