Office 365 - Disabling Focused Inbox in OWA

1. In Outlook on the web, select > Display settings > Focused Inbox.

2. Under When an email is received, select Don't sort messages.

   

3. Click OK.

From: https://support.office.com/en-gb/article/Turn-off-Focused-Inbox-f714d94d-9e63-4217-9ccb-6cb2986aa1b2