I have a regular line chart with custom crosshair & tooltip like this http://take.ms/hAEdp
At random, the line is missing and left with tiny dots. The dots are not any part of my code.
Sometimes, only 1 line is missing as shown here http://take.ms/R97q1 (green color series is missing while 3 others show up correctly)
I get this randomly from time to time, and I don't know how to replicate it. After changing the X-axis range (by button press) the chart renders correctly.
Is this a known bug? How can I workaround it?