CMS preview actions nav broken

[brynwhyman]

Overview

With advanced workflow enabled for a page the CMS preview actions break, in particular:

• The preview actions do not work, e.g split mode, preview mode
• The styling is broken

To recreate

1. Enable workflow for a page
2. Make a change to the content, submitting it for approval
3. View the pending change in the workflow admin, e.g */admin/workflows/
4. Select the page link to be navigated to the page edit view
5. Observe the broken preview actions

Note: Step 4 is crucial

Workaround

Following step 5, refresh the page.

Example

Versions affected

CMS 4.6.0
Advanced Workflow 5.3
Elemental: 4.4
(note this probably occurs in earlier versions)