Is this on the P4 computer in the first post?use Slimjet, which is a chromium derivative. I installed it from a .deb package. There is one problem. Youtube videos drive the cpu to 98% and the video, of course, jumps badly. If I close the youtube page the cpu comes down.
Pepper Flash is usually built into the browser.Pepper Flash Player is maintained by Google, and is newer than Adobe Flash Player. Adobe currently still provides security fixes for Adobe Flash Player. Google provides newer features in Pepper Flash Player. Pepper Flash Player can currently only be used with Chromium (and with Chrome).
That is probably why you are seeing different versions.
I have a P4 processor computer.
Anything I watch on You Tube has to be at a quality setting of 360p to make it run smooth.
The video driver you use can also be a factor.