System Restore to when it worked.
What about all the usual resets in the display control panels?
I've had this laptop for several months. Now, suddenly, the colors on the screen are too light. By this I mean that black looks dark grey, and light grey looks white (anything #E5E5E5 or brighter is indistinguishable from #FFFFFF). For example, in Chrome I can't tell which tab is currently open, and in Gmail the read emails aren't darkened. It's like the value of each color was increased by 10.
This problem started suddenly a couple of days ago. It's not a browser issue; the same thing happens when I test it in my image editing programs. It's not the brightness either. Even with minimum brightness, light grey and white are indistinguishable. Turning the laptop off and back on also doesn't help. When I search around for this issue, I get some results saying it could be caused by an HDMI connection, but I haven't connected the laptop to an HDMI cable in a long time.
A bunch of keys had gotten accidentally pressed a bit before this started, which I'm guessing caused some display setting to change, but I can't figure out what. Does anyone know what settings would cause this? Or could something else be causing it?

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