Twenty Nineteen breaks the Gutenberg meta boxes area

[afercia]

Tested on WP 5.0 (happens also on 4.9.8 with Twenty Nineteen added cloning the repo) and Yoast SEO activated:

The meta boxes area overlaps and almost completely hides the content area:

Activate Twenty Seventeen to double check: everything looks fine.

Suspected CSS rule:

.editor-styles-wrapper {
    overflow-x: hidden;
}