I think there was a thread posted in the Rift section a long time ago about the dangers of sunlight causing damage to the screen but I think it's worth a reminder here.
I've had a couple small streaks appear on my screen, visible in both lenses, small thin diagonal lines towards the top of my vision, which was confusing me... how could the same marks appear in both lenses? they can't be scratches and they don't appear when the Oculus logo comes on but are there when the loading dots appear... i.e. when the whole screen lights up in a very dark grey and are very visible when any bright image is displayed.
So I think this happened when I left my Quest 1 on my bed and the lenses were probably facing the window... as the sun tracked across the sky, it was enough to create a thin hairline mark across the screen. So my advice is always put the headset in its case when not in use, or at least never leave it facing any window.
It's annoying but I think I can wait for the release of the next Quest before replacing it.
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