Just a quick question

I was just using blender 2.8.1 and i pressed CTRL+V and it pasted something from a long time ago so does that mean the blender has some sort of buffer that stays forever? unless i change it right?

Check your “temp” folders

Ok i went to C:\tmp but its only my output video, where can i find the other one you say?

In preferences -> File paths
Check your old blender path and the newest one. Probably the newer blender goes into an “old” tmp folder where the copybuffer used to be. Your old blender should have a different temp folder. That’s my guess