A test pdf with a rectangle and 29 thin lines of equal width is attached together with a png showing the expected and the actual rendering. Expected: in the rendered pdf, all lines should have the same width (as done e.g. by okular 0.9.5 and acrobat). Actual: some lines are twice as thick as the others (which is visually disturbing). Reproducible: Always
Created attachment 92799 [details] test pdf
Created attachment 92801 [details] expected and actual rendering
Confirmed in 0.19.3, used with Ubuntu Gnome 14.04.
Confirmed on 1.11.3