Switching View-File macro between headings to button mode leads to deleted content

[lamblinc]

Steps to reproduce the problematic behavior:

1. Import the page View-file+with+headings.WebHome.zip in an XWiki instance

2. Go into edit mode
3. Change the display option of the first view-file macro to "button"
4. Save the page

Expected behavior
First file is displayed in button mode, second is displayed in thumbnail mode

Actual behavior
Second header and view-file macro are deleted

Environment:

• OS: NA
• Browser: Chromium, Firefox
• XWiki version: 16.10.9, 16.10.9
• App version 1.27.1