It's pretty usual with youtube videos, especially with automatic subtitles that they have two lines on the screen simultaneously, and when the new line comes, it pushes the previous one "up" as the one even before that disappears. This is a pretty useful way of displaying subtitles. Now SMPlayer keeps the existing line where it is, and shows the new line where the disappearing line was. I find this pretty annoying and it makes it way harder to follow, but I realize some people might like the way it's now, so I'd like to ask to have this kind of display implemented and selectable in sub options.
p.s. While youtube-dl doesn't grab the subs now, I'm talking about videos I saved with JDownloader2, that grabs subtitles, too.