Media Adjustments missing

I am having difficulty using the content element “Text & Images” - the images are always sized incorrectly. I assume this could be fixed by using 'the Media Adjustments", but they are missing from the images tab.

They are mentioned in this document, however even the screen capture on this page does not show them:
Working with images — Tutorial for Editors main documentation (

Can anyone shed any light on this?

Many thanks.