Closing preview window still causes jump

[giddie]

1. Open buffer with line 20 at the top of the screen
2. Cursor is on line 40
3. Bottom line is 96
4. :ped
5. Line 20 is still the top line
6. Cursor still on line 40
7. :pclose
8. Line 16 is the top line
9. Cursor still on line 40