I tried that, and all the other suggested techniques, nothing worked. So this morning, just on a whim (no idea why, really) I gently rubbed my fingertip right-to-left across the area where the pixel was lit, and it flickered out and came back on. I did it again, and it went out for a second or two and returned. I did it one more time, it went out and stayed out!

The pressure was relatively light, just enough to see a momentary reaction on the screen behind the fingertip. I'm not betting the farm that this is a permanent fix, but for the moment it looks good.

When I get to be King of the World, I will proclaim January 13 to be Happy Pixel Day, and all will celebrate and rejoice.

tanstaafl.