As a user I want the email import to be most efficient as possible without the need to configure any connection and timing parameters, so that my email import is finished as quickly as possible without blocking other running processes. I still need to be able to use the system for other purposes.

Note: Importing emails from an IMAP account can sometimes (due to e.g. rate limits) take a really long time (weeks, month, etc.), we therefore want to make sure that we use the most efficient way possible when importing emails, especially in the multi-user (company) scenario.

Acceptance criteria

• Emails are imported the most efficient way (highest throughput)
• Email import is automatically adjusted if metrics (server rate limits, amount of parallel connections, connection stability, etc.) change