Selection limits for timing adjustments.

Display the start and end times of selected keyframes or clips, either as a reference or to adjust their duration.

When selecting multiple keyframes or at least one clip, two labels should appear at the beginning and end of these in the timeline of the respective editor, allowing for adjustments to lengthen and shorten their duration.

Although these adjustments can be made by adjusting the time position and scaling, I find this method much more practical, and it also serves as an indicator of the selection's position.