Strange Tiling dark line after update to 4.14.3

After update to 4.14.3 (coming from 4.13) there are this dark lines everywhere, even in new maps.
Also there is a new orrible managment of “z-depth pass overlapping” between faces and everything start to flipping if you are not to close to the object. It seems (but I’m not a programmer so is just a theory) that with 4.14 the calculation is less accurate so the delta of value needed to avoid the glitch it’s increased now. If it’s true can I increase somewhere the accuracy?
I attach a screen for the first issue