Conflict window is displayed when editing a Tour entry page

STEPS TO REPRODUCE

1. Go to http://localhost:8080/xwiki/bin/view/Tour/ and create a Tour or simply import the XAR attached
2. Edit the Tour entry page
3. On 'STEPS' section, click 'EDIT' for a step (e.g. for step 1)
4. Change the content (or title)
5. Click 'Save'
6. Click 'Save & View'

EXPECTED RESULTS

The entry page is saved with the respective modifications.

ACTUAL RESULTS

An editing conflict window is displayed. However, the new modifications seem to be saved.

The issue could not be reproduced on XWiki 11.1.

The bug also reproduced when deleting a step from a tour instead of editing it.