How to disable Mail split screen in High Sierra

Mail>Preferences>General

Hmm... I have this exact setting disabled, have since rebooted my system multiple times (so mail app has been stopped for sure).

But still, when in a full screen window, mail app opens a new incoming mail using split screen. Am I the only one experiencing this?

Case is with Chrome, on any web site when brower is full screen and a pop-up shows a new incoming mail. Clicking on it opens the mail, but still in split screen.

This happens for me too. When I'm in the Mail app it no longer opens emails in split screen since I have disabled that option. However, when a new mail notification appears in the top right of the screen, I click on it and it still opens the email in split screen. I really hate Apple now. Since this No-Choice upgrade to High Sierra I have had so many problems. Using my macbook is a total headache now.

Yes, this is very annoying. Is there any solution to make it stop?

True, Apple's software quality is getting worse each year more. I strongly hope they'll be able to fix this or I may drop Mail as well.

S_Peters wrote:

Thanks.

Good computing S_Peters !

Still having the same issue even after updating to 10.13.2 I wonder whether this problem is even being recognised :-\