FAQ Question #14
When users log into LiveJournal, their usernames and passwords are stored in their browser, in files called "cookies". Scripting languages make it possible to write scripts which can retrieve usernames and passwords from the cookies of those who view the page. Developers have investigated alternate ways of allowing these languages, but have not found a way to allow "safe" scripts while blocking those that create security risks.
In addition to scripting languages, LiveJournal prohibits use of several HTML tags: <iframe>, <embed>, <object>, and some attributes of the <div> tag. Due to these restrictions, it is not possible to embed music, videos, or other active content such as Flash objects into journal entries. If you would like to post entries with music or video files, you will need to upload the files to another site and provide a text link to them.
If you know a way for LiveJournal to allow any of these forbidden scripts or tags without compromising the security of users' accounts, please submit a suggestion by following the procedure described at http://www.livejournal.com/support/faqb
July 14th, 2005 (burr86)
Damn, looks like I won't be using <iframe>...