After resetting course, assignfeedback_editpdf is full

Hi friends,

long time moodle users here. Now Moodle 3.7, going to upgrade to 3.9 soon.

This year we are not going to make a new install, now we are resetting all courses.

After course reset, it's eating too much space, so I reviewed with "course size" plugin and it says assignfeedback_editpdf plugin is over 790MB.

Resetting with moosh -n course-reset xx continues in 790MB

I think it should be 0MB, isn't it?