[laxisOp]

A email is a notification,so how you are in the mood when it will come.can you elaborate clearly

[atrus]

Close the email client. No emails, no notifications.

In the mood for dealing with email, open client.

[nirui]

It's simple, there's this "Star" feature on Thunderbird, so if I'm not ready to handle the mail now, I'll just click the star to mark it as important, and undo the star after I've done handling it.

Or, just like what @atrus said, don't receive emails if you have other higher-priorities.