I’m looking for some kind of “blocker” app/function so I can still work in my Mail app (Apple Mail), but I don’t want new emails coming though while this function is active.
Example: I want to do some email activity during the next 2 hours. During this time I am only allowed to send mail, react to existing mails etc, but I do not want Mail to check for new emails.
Any ideas how to perform this?
In case there’s no way for this, I have simple idea to just set “Check for new messages” to “Manually” in Mail.app preferences.
After you finish working, you can type ⌘⇧N to “Get All New Mail”.
Drawback: you have to continuously manual-fetch for new mails while this settings active. Maybe there’s Apple Script way to toggle On/Off this settings with one keyboard shortcut.
I just set the client to work offline and then the emails I send during that time are sent when I reconnect. Is that a solution?
What you want is not supported by any mail app that I am aware of, but it is supported by
SaneBox’s “SaneDoNotDisturb” feature.
I have been a paying customer of SaneBox since 2013, and features like this are why it’s one of the easiest bills I pay each year.
Thanks for your answers, highly appreciated!
The thing is that I think I have very good control of my emails in the Mail app, so I don’t feel the need of any fancy AI or such. I tried Sanebox a while ago but couldn’t be friends with it, I have also tried many of the other email apps on the market but I always fall back to Mail.
Thought:
Since a couple of versions ago Apple opened up for extensions in Mail. It seems that this market isn’t really big, which I think is a shame. Why is that do you think?
The “Don’t disturb” function and the “Boomerang” function are two functions I’d be happy to pay for, while I keep Apple Mail as my Mail application of choice. Someone should create these as extensions to Mail. 
Just to elaborate a little bit more on this, you can take all of your mailboxes offline in Apple Mail via the menu Mailbox > Take All Accounts Offline.
You can automate taking your accounts offline and back online via a pretty simple Keyboard Maestro macro.