Problems rendering iframe embed code in Media column from streaming media sites

[GrantsTracks]

Hi there,

I'm working an a tutorial for TimeMapper and have been testing streaming media links in the MEDIA column. All the iframe embed code from YouTube, Vimeo and Dailymotion produce some kind of error when the code inserted into the MEDIA column and rendered by TimeMapper.

But the same code does work when inserted into the DESCRIPTION column and rendered. All examples also work when inserted in a WordPress post as well.

This makes me believe the iframe code itself isn't the problem, but that there's something specific in the MEDIA column that is getting in the way of the streaming media being able to be displayed correctly.

Is this a known issue? Might there be a work around that you know of?

Thanks very much for any help you can give me.

Here's a link to the TimeMap I produced with only the date, title, media and description spreadsheet cells filled in.

http://timemapper.okfnlabs.org/grantwi47155121/gsw-timemapper-media-test

Here's the example embed code I was using.

YouTube
<iframe width="560" height="315" src="https://www.youtube.com/embed/R4FNSSvNnV8" frameborder="0" allow="accelerometer; autoplay;" allowfullscreen></iframe>

Vimeo
<iframe src="https://player.vimeo.com/video/112866269" width="640" height="360" frameborder="0" allow="autoplay; fullscreen" allowfullscreen></iframe>

Dailymotion
<iframe frameborder="0" width="480" height="270" src="https://www.dailymotion.com/embed/video/x2p0ate" allowfullscreen allow="autoplay"></iframe>