Non default editor XWiki.XWikiComments class is always overriden

Step to reproduce :

• Change the default editor in XWiki.XWikiComments page, for Plain text or Wiki
• Go back on any page of the wiki, the comments field is Plain text or wiki as expected
• Post a comment
• Post another comment: the comment field is showing WYSIWYG (whereas we would expect Plain text or wiki again)
• Go back on XWiki.XWikiComments page, the editor setting is back to default again (which means WYSIWYG), our setting has been overriden.