Outlook Web Access, OWA - If it is set to LITE mode some functionality is limited.
This is controlled by
OWA – Options – Settings – General –
Accessibility – Check mark for Blind and Low vision should be blank.
The ‘Accessibility’ option is not visible unless Lite is already selected. So if you don’t see Accessibility on the left side, just select GENERAL and it will be buried in there.
Here is a link to see what it looks like.