The navigation popup repositions on open for popups which are on the edge of the page, which is a bit janky. Here's a GIF of the experience, click through to see
When the navigation popup is opened, it is positioned to where the user's mouse is in Navpopup.showSoonIfStable and then repositioned when the limitHorizontalPosition function is invoked, which is set on an interval.
A naive suggestion is call limitHorizontalPosition within showSoonIfStable, but I'm not sure that's the best solution.
How can I run my own development version of the script to tinker with the implementation to fix this bug?