Go back w/Ctrl-N. Sliders aren't where I left them

Saw this last night in 1.31:

  • Ctrl-N, Convert. Ctrl-N, move a slider, say Brightness -5, Apply.
  • Ctrl-N again, to make further adjustments. Note that the Brightness slider is showing zero, but the image looks like -5 as desired.
  • OK, I wanted Brightness -6. Go to move the slider negatively again, an get surprising display. At -1, image brightens way up.

When I go back, I expect to find the sliders where I last left them.

Last night, they didn’t. This morning, A-OK. Will keep watching.