Option to opt out scanning of all folders

Feature Proposal
1

Expected behavior

I’d like to see an option to opt out the scanning of all IMAP folders.

Actual behavior

Right now, every IMAP folder is scanned from time to time.
For me that’s really messy because I automatically store emails
from newsletters and some mailing lists outside of =INBOX but
they still appear in Delta.Chat

2

I also would like this feature. Because I use a extensions address an a server sided filter to move all mails adressed to this extentions address into the DeltaChat-folder.

Maybe the “spam folder” should always scanned to never miss a message.