Summary

Navigating any screen with the Rich text editor allows you to get to the editor, but once inside you can not move back with Shift-Tab.

This creates a problem with navigation when a mouse can not be used for navigation (for example when the NVDA screen reader is used).

Environment
Customer's reported environment:
Firefox : 62.0.3
NVDA : 2018.3.2

We have tested with Firefox 62.0, Chrome 69.0.3497.100 and Safari 11.1.2.

Steps to Reproduce

1. Install the NVDA screen reader
2. Open any screen that contains the Rich text editor
3. Navigate to the editor using the Tab key
4. Once inside the editor, use the Shift-Tab key to try to navigate backwards.

Expected Results
Shift-Tab should move back out from the editor to the previous step.

Actual Results
Shift-Tab doesn't do anything and the cursor remains inside the editor.

Note
This only happens under the Visual tab in the editor. In the Text tab you can still navigate back with Shift-Tab.

Workaround
The only known workaround to date is to completely disable the Rich text editor under Administration > System > User interface > Rich text editor