"...?ecver=x..." parameter on the youtube embed URL

Question

I've Noticed when embedding Youtube videos the following 2 URLs achieve the same result:

https://www.youtube.com/embed/ML1AyQC2HKM?ecver=2&modestbranding=1&rel=0
https://www.youtube.com/embed/kwdRYaBUco4?modestbranding=1&rel=0

embeded youtube video with parameter set

What does the ecver parameter on the youtube embed URL set ?

After checking The Documentation and searching the internet I couldn't seem to find anything to explain this parameter.

The name would suggest its setting the Ecmascript version? but this is just a stab in the dark and i can't seem to find anything to confirm this.

Inquisitor

Answer 1

ecver=1 can be deleted. This is a forced display at the top of the video title, + watch later, + share.

Ballonet

Answer 2

The ecver=2 is for getting rid of ads on pausing the video - like the rel=0 is for having no ads at the end of the video, but this seems to work no more.

Remuneration