I did some troubleshooting on my own today and I’ll share my observations.  First pictures of the problem.  Pay attention to the hearthstone in relationship to the guide.

    Proper Alignment

    After reload/login/first guide load

    This test was done using only Dugi enabled to rule out conflict.  There are 3 scenarios in which I noticed movement.

    MultiStep + Anchored:
    When I turn off multi-step mode the window position doesn’t move.  The movement still occurs if there’s only 1 step or if World Quest Tracking Guide is enabled.  My theory is the dynamic nature of that Multi-Step window is adjusting size from the center, but the anchor remains at the top.

    The easiest way for me to test this was using tabs, I’d select a blank tab (no guide loaded) and then select the a tab with a guide and you can see the window change beyond where it should be anchored (in this case upwards).  It would take another reload to cause it occur again.  Having a guide already enabled would still change the window position, but happened while the whole interface was loading.  It’s odd that on my other computer (son’s/1080 vs 1440) it’s shifting downward gradually.

    Anchored, no Multi-Step
    After several reloads with just Multi-step turned off, the frame moves the opposite direction, albeit only a few pixels per load.

    With Elvui loaded, this shift once again goes upwards — no idea there  

    Anchored off & Multi-Step Off
    Same as above, moving very slightly after each reload.  This is one tough to replicates, most times with both off there’s no movement at all

    Currently running without anchored or multi-step enabled to minimize movements.  Also making sure I log off with no guides loaded (blank tab)