Anybody met the same problem? Can't finalize a LP without using Rich Text Editor.
I've tried to open on Safari/IE/Chrome for Mac, none worked, but when I did it on a PC, it works. Strange.
I think your LP includes special character is not specified in utf-8.
MS Windows has be extended about some characters and marketo can not check enough.
Thanks you Takehiro, So what should I do to resolve the problem?
I recommend you contact support.
In my case, Marketo support gave me an internal technical information and a workaround about international languages.