Let the browser choose the protocol
You should deliver all web content over https. In 2021 browsers are displaying increasingly obtrusive warnings when content is delivered over http.
Use protocol independent URLs whenever possible so that the browser will choose the protocol related to the protocol which the page is delivered with.
Example issues
- When your page is delivered via
httpsand you provide a youtube video only viahttpthe most browsers (e.g. Firefox, Chrome) won't display the video. - When you deliver your youtube video via
https://youtu.be/jyElDp98HdIyour test which checks that the embeded video is rendered in the view will fail because your test server doesn't use https
Solution
Let your links look like //youtu.be/jyElDp98HdI and you will be fine, server side and test side.