Mailspring 1.13.0 now runs on Electron 22, completing a migration process we started in 1.12.0!
If you are upgrading from an old version of Mailspring, download and run 1.12.0 first before installing this version. We've moved from keytar to Electron's safeStorage API for securely storing your email passwords, and version 1.12.0 will perform the migration.
If you're using the snap version of Mailspring, you may find that Mailspring forgets your passwords when you upgrade. I'm very sorry for the hassle this causes - issues with the 1.12.0 release caused the snap version to lose your passwords during the migration in many scenarios.