Running the most latest version of WordPress -- found that when adding the new YouTube embed code that it would disappear out of the post editor when switching between the "HTML" and the "Visual" tab. Rarely and randomly the code DOES preview on the "Visual" tab but disappears when adding a carriage return (hitting "enter") while editing text below. They do seem to be able to be uploaded though, if you hit "update" on the post while the new code is in the "HTML" editor tab, but then the code can disappear again if you try to edit the post again.
**NOTE** I am talking about the NEW YouTube code which looks like this:
<iframe title="YouTube video player" class="youtube-player" type="text/html" width="560" height="345" src="http://www.youtube.com/embed/vQf4IybnSZA?rel=0" frameborder="0" allowFullScreen></iframe>
I have tested this will all of the plugins deactivated as well as on a different theme. None of the "code" tags in the Post editor keep the embed codes from dissapearing.
This issue occurs in all browsers, however through the Developer Tools on Chrome I have been able to see that there is an error that says
Failed to load resource www.youtube.com/embed/vQf4IybnSZA?rel=0 Failed to load resourceon the post editor after switching from the "HTML" view to the "Visual" view (which makes the embed code disappear).
This style of old code still works just fine, and does not disappear:
<object width="560" height="340"><param name="movie" value="http://www.youtube.com/v/vQf4IybnSZA?fs=1&hl=en_US&rel=0"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/vQf4IybnSZA?fs=1&hl=en_US&rel=0" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="560" height="340"></embed></object>
But we need to use the NEW code. Anyone know the answer to this?