i have this same problem. i notice it only at night. i have those glow in the dark stars stuck to my ceiling and when the lights are off n i stare right at it, it disappears within about 2 seconds... its not immediately gone. if i want to see it, i have to look right next to it and itll show up.
in the light, there's no problems.. i think i read somewhere that its normal for it to happen in darkness.. if ur having problems during the daylight hours, id go immediately. maybe ill go now that i think about it.
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