The light version of Outlook Web App is optimized for accessibility, including for users who are blind or who have low vision. The light version provides fewer features than the regular version and is sometimes faster.
Click Options > Settings > General.
On the General tab, under Accessibility, select Use the blind and low vision experience.
Click Save or press CTRL+S to save your changes.
Sign out and sign in again to complete the change to the light version.
What if I want to know more?