Follow this steps to reproduce:
- Edit a wiki page using either the Wiki editor or the WYSIWYG editor (doesn't matter)
- Make a change and click Save (to save and remain in edit mode)
- Click on a link from the breadcrumb
- Click Back (browser button) to return to edit mode
- Make some change and click Save & View (this time) to save and go to view mode.
You get a save conflict warning message.
Reproduces on both Firefox and Chrome.