Hello, with yesterday's and today's ccpnmr2.1/python/ccpnmr/analysis/frames/WindowFrame.py update there are no more crosshairs visible on the spectrum canvas except for the small one on the axis. Changing: handlerExc = GlHandler.error # below was for when we had GL_EQUIV handlerXorColor = (0.0, 0.0, 0.0) # below is for GL_XOR #handlerXorColor = (1.0, 1.0, 1.0) back to handlerExc = GlHandler.error # below was for when we had GL_EQUIV #handlerXorColor = (0.0, 0.0, 0.0) # below is for GL_XOR handlerXorColor = (1.0, 1.0, 1.0) made it work again. Bye Tolga