https://support.google.com/youtube/answer/9884579 - How to add chapters to a progress bar.
The most important are:
- having the first timestamp starts with 00:00.
- At least three timestamps listed in ascending order.
- Minimum length for video chapters is 10 second.
https://support.google.com/youtube/thread/49733199?hl=en (about Video Chapters - 6 days ago posted)
https://support.google.com/youtube/thread/18138167 (history of experiment)
YouTube has introduce the Video Chapters available to be seen in the progress bar.
I have noticed it some days ago..., although I don't remember when I first upload this video in early April 2020, is it automatically appear or not, but I felt that time it was showing 'not correct' as very short description of 1K, 2K is ignored. After being changed to 'Distance 1K' or 'Distance 2K', now all appear.
Go ahead see it yourself (sorry for the same video you might already knew several times!):
(Require to watch it in Full YouTube's website - thumbnail in Vegas forum not working!)
Put markers in your Vegas Pro, along with description.
Ctrl-Alt-4 or go to View -> Window -> Edit Details, Show Markers only, then click on the top-left cell to highlight everything. Copy (Ctrl+C), and go to notepad or preferred text editor to paste it, then remove frame numbers as it is not needed.
I personally use VASST Ultimate S Pro to export these markers to text format, so then it can be pasted to YouTube's description, just make sure you also have 00:00 marker as well.
I don't use Vegasaur, but similar function is also available: https://vegasaur.com/markers
Hope helps to you, YouTubers!