Datepicker positioning in Chrome inside Fixed element when font-size is not 12px...and more

I've got a very specific bug that only happens when I have a datepicker in a position: fixed element and the html font-size is not set to 12px and the root scroll container is not scrolled to the top.

• It works correctly in other Chomium browsers like Edge.
• It works if the font-size is exactly 12px.
• It works if the element it is in anything other than a position: fixed element (such as position: sticky).
• It works if you are scrolled to the top of the page.

It happens in both 1.12.1 and 1.13.0.

I know it's a pretty specific issue that I'm not sure how easy it will be to reproduce. I'll try to set something up. But I'm hoping the symptoms might be enough for someone who knows the code.

In the meantime, is there a method that can be called to recalculate the position? Or is there an option that can be set to tie the position/scroll linkage to a certain parent (other than the root element? (sometimes scrolling the main window doesn't move the element the picker should be attached to, yet the picker scrolls).

Start by reproducing the datepicker positioning issue in Chrome with a non-12px html font size, a position: fixed container, and the root scroll container scrolled away from the top; compare the reported behavior in Edge and other container positions. No file or test is named, so trace the datepicker positioning entry point and determine whether the picker follows the correct element while scrolling.