Hi nikamela and welcome to the Forums!
I'm guessing at your video artifact but it could be screen refresh syncing.
In-game, click Esc and then the Options tab (looks like a game controller).
Scroll down a little less than halfway and check the box next to VSync (it's right above the Menu Scale and Zoom Level options).
I highly recommend also lowering the Zoom level to 75% at the same time to see more of your Farm on the screen.