It now reacts to changes within the same process.

Account switching still doesn't properly update the view...

Of course accounts can be of various granularity:

• there might be vanilla smtp or ldap accounts, that provide nothing else and require full configuration
• there might be a kolab account that comes with imap, smtp, ldap
• there might be a generic imap account that comes with imap and smtp.
• there might be a jmap account that provides everything but communications only over jmap

SMTP should be in Sink because:

• Access is backend specific
• smtp might be replaced with another mailtransport protocol (and the client shouldn't care). E.g. JMAP has a mechanism to send mail
• the sent mail folder is with the resource as well
• mailtransport may move to the server
• The outbox needs to be persistent, and browsable similarly to a folder

LDAP Should be in Sink because:

• Access is backend specific
• It provides contacts in addressbooks (just like a regular addressbooks), so we should have one query API.
• The configuration for ldap belongs to the same service.

https://phabricator.kde.org/project/view/62/