Add a Video

Preceden currently does not support embedding videos on your timelines. Your best bet is to paste the video's URL into the event notes. Preceden will automatically convert that URL into a link, so anyone viewing your timeline can click it to watch the video:

To show something other than the raw URL, write the link with Markdown so it displays the words you choose: Add a Link to Your Timeline.

Where the link shows up

Event notes appear in the popup that opens when someone hovers over the event, and in the event list below the timeline. The popup stays open while the cursor moves onto it, so the link is still there to click, and it opens in a new tab, which leaves the timeline where the viewer left it.

If the note does not appear at all, click Appearance above your timeline, open the Content Visibility section, and check Notes under Display in Popup & Event List. There is a second Notes checkbox under Display on Timeline that prints the note on the event itself, and that one is off unless you turn it on.

A video link reads better with a picture beside it, so consider adding the video's thumbnail to the event as well.