Misaligned popover arrows

Created by: simonihmig

Seems similar to #23793 (closed), although I could not reproduce the issue for tooltips, but indeed for popovers.

Here is a demo: https://codepen.io/simonihmig/pen/WdxXja. The first button triggers a popover, where you can clearly see that the arrow is misaligned.

It has left: 132px applied by popper.js. However the popover itself has a width of 276px, so the center should rather be 137px. And indeed if I set this manually to this value or left: 50% in Chrome Dev Tools, then it is perfectly aligned! So somewhere this 5px offset is causing the misalignment.