Tabbing through two inline editors throws TypeError: Cannot read property 'contains' of null

[bradbalfour]

Are you reporting a feature or a bug?

Bug

https://dev.ckeditor.com/ticket/17028

Provide detailed reproduction steps (if any)

1. Create a page with 2 inline CKEditors
2. change text in the first editor
3. tab out of the first editor and into the second editor
4. tab out of the second editor

Expected result

CKEditor works with no errors

Actual result

Uncaught TypeError: Cannot read property 'contains' of null
    at c.getContext (ckeditor.js:696)
    at c.<anonymous> (ckeditor.js:701)
    at a.h (ckeditor.js:10)
    at a.window.CKEDITOR.window.CKEDITOR.dom.CKEDITOR.event.CKEDITOR.event.fire (ckeditor.js:11)
    at a.window.CKEDITOR.window.CKEDITOR.dom.CKEDITOR.editor.CKEDITOR.editor.fire (ckeditor.js:13)
    at window.CKEDITOR.window.CKEDITOR.dom.CKEDITOR.keystrokeHandler.f (ckeditor.js:227)
    at g.h (ckeditor.js:10)
    at g.window.CKEDITOR.window.CKEDITOR.dom.CKEDITOR.event.CKEDITOR.event.fire (ckeditor.js:11)
    at HTMLDivElement.<anonymous> (ckeditor.js:57)

Other details

• Browser: Version 58.0.3029.110 (64-bit)
• OS: Mac OS X v10.12.5 (Sierra)
• CKEditor version: 4.6.2
• Installed CKEditor plugins:

[mlewand]

Duplicate of #424.

This has been fixed in 4.7.1.