When developing in Unity, using the TileMap feature can sometimes result in visual tearing or splitting, as shown in the image below.
To resolve this issue, various methods exist. You can create a material and enable Pixel Snap, or change the Grid coordinates...

However, even when applying known methods, the issue can be resolved by setting the MSAA item in the Camera component to Off, as shown in the image below, which eliminates the tearing problem.

There you go. You can see the problem is resolved cleanly as shown below.
Neat, right?

MSAA stands for Multi-sample anti-aliasing, and it seems to cause splitting issues during the anti-aliasing processing process.
https://docs.unity3d.com/Packages/com.unity.render-pipelines.high-definition@6.7/manual/MSAA.html
I hope the above tip is helpful when you are developing.
Thank you.