Weird lines in tilemap

Good day.
I'm making a 2D game. I've used tilemaps to build the levels, and they worked perfectly. I used to have problems with them, so I created a material with Pixel Snap and it worked. However, today, when I opened up my project, weird lines started appearing in every scene, but ONLY in the scene view, NOT in the game view.

I've tried to disable anti-aliasing, but the button is not there in quality settings.
Decreasing/Increasing my Pixels per Unit / Grid size on the tilemaps has not worked.
I've already got the tilemaps sprites marked as Point (no filter)

It's very odd. It only happens in the scene view and I don't know how to fix it:

Picture:

Does anybody know how to fix this? It's very annoying.

 

this

 

Thank you for your answer, but it did not work. As I've stated, this error is only present in the Scene View and not when running the game.

On another note, the Anti Aliasing option does not appear in my Graphics Settings and I don't know why.

I've done the material thing, and it works if I uncheck Pixel Snap, but then black lines appear in-game, and viceversa.