Sidebar select, textarea and input width not working

Hello,

that's weird – after updating to the newest version yesterday I found the selection field not compressed but too long. The 100% width is overflowing my sidebar. The edit field has the right width.
Also the wrapper ".rwmb-input" has the correct width, but the selection input inside is to wide.

I have noticed that "box-sizing: content-box" is the culprit.
It comes from

.edit-post-sidebar *,
.edit-post-sidebar :after,
.edit-post-sidebar :before,
[...]
{
   box-sizing: inherit
}

Have you also observed this behavior?
I have disabled all custom admin styles.

Edit: For now I have overwritten .rwmb-select with explicit "box-sizing: border-box"

Juergen