If you would like to post a video, click on the third icon above the text box - the one which is to the left of the T-icon - It's called "MEDIA". Just move the cursor over the icons and you will easily detect the right one.
When you click it, a blank box appears in which you are supposed to paste an EMBED code.
At youtube it's easy to get an embed code: Click the "Share" button beneath the video and then "Embed". The text which appears in blue is the embed code.
Copy the code, then paste it into the white box which appeared when you clicked the MEDIA button. Click "OK" and "Add reply" - and the video will appear where it's supposed to be :-)
If it does not readily appear - please click the REFRESH button before you remove the comment or the whole discussion! With Google Chrome, for example, a newly posted video does not show immediately!
I'm looking forward to watching your videos :-),
Sonja Myriel in co-operation with Steven Bluestar, who I would like to thank for the illustrating pictures!
Thank you Dear Sonja xxx