Jagged edges on a cube despite 8x anti-aliasing

Hello there! I was messing around a random project and everything was working perfectly, when all of a sudden jagged edges appeared on all objects. I’ve been trying to resolve this issue for the past two dails, only to no avail. I have tried changing various settings, when at last I’ve uninstalled unity and removed all projects. After re-installing it, however, the problem still persists.

One more thing to note is that the cube is displayed properly in scene view, but with jagged edges in game view… why?

These are the camera properties:

More properties included in the comment, since no more than two attachments can be attached.
Thank you for your time in advance.

These are the cube properties:

These are Quality settings: