Why doesn't folder on Start screen disappear after removing all the tiles from it?

[Windows Central Question]

There's a folder on my Lumia 1520 (OS version 8.1) Start screen that has no tiles/apps in it. I previously created this folder to store multiple apps, but recently removed all of them from the folder. However, the folder did not disappear as it should after removing all the tiles/apps.

What you see in the folder are "empty" tiles, that appear as my chosen Start background. In other words, it looks like the empty tiles you'd see in a folder that has not been completely filled with apps. The upper left tile however, is solid, or dark (i.e., not my Start background), and when tapped, results in the two horizontal bars dropping down, where the top bar is used to name the folder. Whether or not the folder is named, tapping again to close those bars always results in the upper left tile being solid, not matter what size you make the folder.

The folder can be re-sized as normal.

What I've tried to make the folder disappear: (1) soft reboot, (2) completely filling up the folder with tiles/apps, then removing them. I've also created a totally new folder, which disappears as normal once all the tiles/apps are removed.

I wonder if the folder has somehow been corrupted.

Any suggestions as to how I can make this folder disappear?!