Negative values in subtitle Vertical Alightment

Noticed in the recent change (upgrade to v8.3), subtitles are displayed right above the bottom line of the video frame, so subtitles are covering video content all the time, which is not the case previously. The position of the previous subtitle is always referring to the bottom window frame, so when I shift the video frame to the top, subtitles are showing over a pure black background, which is nicer since it does not cover video content, it’s more readable and less disturbing.

Not sure if this change is a bug or intentional, but please return us the opt to display subtitles on pure background like before. Maybe negative values of Vertical Alignment?

Some update, it’s weird imo: