How to sync my local mailboxes on my mac to icloud?
I had moved and organized all my important emails from inbox to new mailboxes "On My Mac" since the years before the "Cloud" was exiting. Now I can't access those info when I'm use other device to check mail, I can only see the mails that synced to icloud. How can I sync the old mailboxes which are located inside "On My Mac" area?
iMac 27" 5K, macOS 10.14