When the mouse cursor over the curve, the curve is highlighted and thicken. When the Draw Lines Smoothly turned off, sometimes highlighted the grid and also thicken. When the Draw Lines Smoothly on, everything works fine.
It looks like the background grid is being drawn in thicker lines than it should in the screenshots when smooth lines is off vs. 9.5. Haven't been able to verify that on my build, though.
andrey_vl this happens time to time (2-5sec) for pan, zoom tool or select curve, keyframe. h10.0.249.5
I see the reference grid lines are thicker than normal in the screenshots you posted but I could not reproduce the problem. Which action were you doing when the lines started being drawn thicker?