How can I embed a video in the questionnaire?

To embed a video you first need to upload it to YouTube, vimeo.com or wistia.com.

(when using YouTube it needs to be a public video - per their terms of service it's not allowed to embed an "unlisted" video)

Then you can add a new element to the questionnaire in the place you'd like the video to show up:

Add something (e.g. "video") in the label, and click save. (the label will not be shown in the questionnaire)

Then click edit again and input the unique identifier of the video (the dialog screen will explain where to find it):