Thanks for the feedback! This is somewhat of an exceptional case in that the “Blank” icon is literally an empty icon. The glowing effect is applied to the icon, so if there is no content within the icon then there won’t be any glowing.
I’m hesitant to add extra logic just for this one icon, so I think the recommended approach would be to use an actual icon if the glowing effect is desired.
The following icons will be included in the next beta release: