With the latest version of Bartender4 the bags have now repositioned themselves to the far right side of the screen. Prior versions as long as you have the two right hand bars enabled in the default UI the bags would be to the left of them, now it shows them on top of them. I'm going to review the changes to try and figure out what changed.

Looking into this, it has to do with how you're hiding the default bars now, as the bag position is based off a call to EditModeUtil:GetRightActionBarWidth() (which returns all kinds of funky values with Bartender4 loaded which is why bags sometimes are in middle of screen and sometimes off the screen). I tried actually overriding that function and returning the proper value for my screen size, which does work, but it severely taints things. I'm going to keep looking at it.

There is something weird going on with Edit Mode and positioning, because just hiding the bars should not screw with their position data - and its also somehow a transient failure that fixes itself shortly after.

Regardless, hiding the original bars is mandatory to prevent taint and other freaky errors, but then again GetRightActionBarWidth does not actually check if they are visible (the MultiBar3_IsVisible functions only check if their config is enabled)

Additionally, there is no way to know where any given user has their bars positioned. Personally, I really don't like the side bars, so I never use them - or rather, reposition them with Bartender.