Expand the functionality of Alt/Opt + Up/Down so editors can quickly bump caption segments to different subtitle tracks using only the keyboard.

Currently, the "Nudge Clip Selection Up/Down" keyboard shortcuts (Alt + Up/Down on Windows, Option + Up/Down on Mac) work perfectly for standard Audio and Video tracks. However, this functionality completely ignores the Subtitle/Caption track ecosystem.

If an editor selects a caption segment and presses Alt + Up, nothing happens. To move a subtitle to a different caption track, editors must manually click and drag the clip with their mouse.

This manual dragging introduces a significant risk of human error; it is incredibly easy to accidentally shift the clip horizontally on the timeline while dragging it up or down, instantly throwing the caption out of sync with the precise audio cues.

why it matters?

Accuracy and Sync Protection -  Using a keyboard shortcut ensures the clip moves strictly on the Y-axis (vertically). Forcing editors to rely on the mouse to drag clips between tracks introduces the constant risk of accidentally nudging the clip on the X-axis (horizontally), which destroys the timing of the subtitles and requires extra time to fix.