Broken less code when saving FlamingoThemesCode.ThemeClass

FlamingoThemesCode.ThemeClass uses the default editor for the lessCode property. If the default editor is WYSIWYG, then editing the lessCode property in object mode will change the original content which will broke the theme.

A simple solution would be to set the editor parameter to Text/PureText.

Note: We can still change the default editor on the user profile.