What is your operating system? Windows 10
What is your Shotcut version 21.02.27
Can you repeat the problem? If so, what are the steps?
- Add Mask: Simple Shape to a clip.
- Add Horizontal and/or Vertical keyframes.
- Delete the keyframes:
The mask moves to the far left side of the screen and/or to the top of the screen.
- Adjust the H & V position even a little and the mask returns to the center.
It could be a known bug, because someone told me he sees the same behavior on his Mac, using an older version of Shotcut.