This problem has only just begun to surface today. Every YouTube video I clicked took two loads before it could start playing. The video restarted at the beginning when I clicked back to the same video tabs after letting it play in the background while I switched tabs, and it did it again.
The issue only briefly remained when I simultaneously went from one YouTube tab video to another, but the video kept starting over every time.
I have several extensions in my browser but this problems started today and those extensions have being installed months even years.