I made a short video to show you what I mean but I find no way of uploading it here.
But the thing is, yes I prefer subtitles, it's a really easy to understand feature. But it's still true what I said. With 1 line, it's located at the very bottom, with 2 lines they are elevated as if there was an invisible third line at the very bottom.
And yes, I know about the format tab. It's aligned to the bottom in the format tab and the vertical margin is 0. (If I could only make the vertical margin less than 0, but I can't.)
https://www.dailymotion.com/video/x7o4238
Uploaded to Dailymotion. This is what I mean, this is how it is for me as soon as I press "Enter". I can't get the lower line of the 2 lines to actually go to the bottom.