Bugged laptop

[Rubixxxx]

I have a laptop for school and i left it unattended for one second (it was locked) and one of my classmates changed a function on the lock screen that activates a high contrast mode for people with bad vision. he deactivated it again afterwards, but now my laptop somehow has a mixture of contrast mode and normal one, resulting in some text being white on white and most tabs looking really bad.

I already tried: activating dark mode in settings of the browser, the normal settings and the login screen; Resetting my browser data; restarting the laptop; redoing all steps my classmate did in hopes of redoing it. Nothing worked, does anyone know a way to fix this? It also sometimes seems to be good again, as if it was somehow randomized. Sometimes when i power my laptop on, nearly everything works, and sometimes i turn it on and everything is bugged

This color is apparently blue:

this is how a normal OneNote page looks like: 

[Rubixxxx]

Quote

bro wtf, i wrote this like 1 month ago, why is nobody responding, please, i dont wanna have my laptop be like this

 

[Tridefender]

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