HTML being stripped out

I'm attempting to add some HTML to the Footer Text field, under Configure Theme. Problem is that the TinyMCE editor is stripping most of it out. I'm not sure on what basis.

It appears, without fully testing, that it is stripping out anything with an image in it..

Could someone clarify how this works, and advise if there is anyway to alter this behaviour?

Check your HTML filtering settings, under Settings > Security.

There you can turn filtering on or off, and also see and edit the elements and attributes that the filter allows.

Thanks, that's what I was looking for :)

Even after adding img to the allowed elements, and src and alt to the allowed attributes I was still having the same problem.

Disabling the filtering works though.