In content apps like contacts or tours, in Magnolia 5.7.x it was possible to expand the detail sub app of a content app to the full width of the viewport. With that, editors could handle easily large texts in rich text editors, too.
In Magnolia 6.2.x this option is missing and the editor must live with the smaller default size of the input fields.

M6 provides the expand option for dialogs only: MGNLUI-5792

Reproduce

1.  Go to a content app, for example, the tours app-> https://demoauthor.magnolia-cms.com/.magnolia/admincentral#app:tours:detail;/magnolia-travels/Kyoto:edit
2. Try to expand the rich text field, but notice that the option is missing and there is plenty of blank space on the right

This was available in Magnolia 5.7, not only to expand the rich text field but the whole content app:

Notes
Closed as won't do. Instead the focus will be on the RTE. The maximize plugin should be available everywhere.