motion detection mask changes over time

[jennjwang]

I have a weird problem. The motion detection mask I use changes over time. It is like shifting downwards. For example, on the grid, I counted the number of masked blocks and open blocks in the first column. This is the result:

t0: 26 masked, 4 open, 12 masked
t1: 27 masked, 4 open, 11 masked
t2: 28 masked, 3 open, 11 masked
t3: 30 masked, 3 open, 9 masked.

I did not edit the mask in between.

MotionEye v0.43.0
Motion v 4.5.1
OS Ubuntu 22.04

[strawberry-poodle]

I will have a go at this one now