SUMMARY
When there are more tracks than can be displayed on the timeline at once, trying to drag a clip to the bottom track results in the timeline view scrolling up. Please see the attached video.

STEPS TO REPRODUCE
1. Create a large number of tracks, more than can fit in the timeline view at once (vertical scrolling must be used to see the remaining tracks).
2. Vertically scroll the timeline so that the bottom track is visible.
3. Drag a clip from the project bin to the bottom track.

OBSERVED RESULT
When the dragged clip crosses the boundary between the project bin and the timeline (assuming the project bin's default position above the timeline), the timeline view scrolls up automatically, and the bottom track is no longer visible.

EXPECTED RESULT
The view shouldn't scroll up when a clip is initially dragged onto the timeline.

SOFTWARE/OS VERSIONS
Linux: KDE neon 5.22 User Edition
KDE Plasma Version: 5.22.2
KDE Frameworks Version: 5.83.0
Qt Version: 5.15.3

ADDITIONAL INFORMATION
This bug happens with 21.04.2 both from neon packages and the AppImage, and also with the latest daily AppImage (8ecff03).