Preview timelapse not working

I did several videos and today I saw that there is a possibility to get a preview of a timelapse. Unfortunately it id not work. Here the configuration:

For octoprint:

  • Raspberry Pi 3 Model B Plus Rev 1.3
  • octoprint.version** : 1.6.1

I have a PC with Windows 10 and using Chrome for Octoprint.

Videos are all done in the past with OCTOLAPS and working very well if I download the *.mp4 file and use VLC to view the video on my PC.

If I use the preview window in Chrome it always looks like this:

Black, no video shown.
Any idea if I can configure something or need a plugin for Chrome ?

Thank you in advanced