What could be causing this bug in chrome?

Question

Google Chrome

Kind.
For a long time I began to notice that in chrome there are such "gaps" between elements.

In the same Firefox, there is no such thing.
Such a bug appears after "scaling" the web page.

Answer 1

There can be no bug in principle. Give a link to the page, we'll see what the problem is.

Answer 2

Indeed, it looks like a chrome bug.
In your case, the easiest way to cure it is this:
.header { background-color: black; }