Currently it's only possible in text mode.
Be able to do this without loosing anything would mean:
- get the content of WYSIWYG as wiki syntax
- unload the WYSIWYG if its 1.0 WYSIWYG
- ask server for conversion and receive the converted content
- load the WYSIWYG if it was not already a 2.0 WYSIWYG
- insert the new wiki content in the new WYSIWYG
Related to CURRIKI-4067.