The iModel is loading spinner and prompt is centered using "position: fixed" relative to the window, rather than the container containing the viewer.
In this image, the spinner should be contained within the white box, but it has moved to the center. When the iModel is finished loading, it stays contained within the white box.
The iModel is loading spinner and prompt is centered using "position: fixed" relative to the window, rather than the container containing the viewer.
In this image, the spinner should be contained within the white box, but it has moved to the center. When the iModel is finished loading, it stays contained within the white box.