I use a web-based CRM system and it has some tools I can include in iframes in my WP pages. Thing is, I have to add them in HTML view because if I do it with the visual editor, the editor deletes the code for some reason, so I was wondering if you could add a new shortcode to show an iframe of a width and height with a src URL and it is shown inline with content. Just something like
[iframe src="whatever.url" height="whatever px or %" width="whatever px or %"]