Can you verify if you get the same results when you do the following:
- click curves under colors menu
- dialog appears, channel value, logarithmic mode, preview enabled, and
curve type smooth
click once anywhere above or below the line in the graph display,
the line will add a point, and snap the line to the point,
but nothing occurs in the image preview.
If you click a second time, a second point is added and the preview updates
Now drag the line for the first point, preview works fine.
I tried in linear, same results.
Freehand displays preview correctly.
Should only the dragging method be used.
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